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NAME

       gpg - OpenPGP encryption and signing tool

SYNOPSIS

       gpg [--homedir dir] [--options file] [options] command [args]

DESCRIPTION

       gpg  is the OpenPGP part of the GNU Privacy Guard (GnuPG). It is a tool
       to provide digital encryption and signing services  using  the  OpenPGP
       standard.  gpg  features  complete  key  management  and  all bells and
       whistles you can expect from a decent OpenPGP implementation.

       This is the standalone version of gpg.   For  desktop  use  you  should
       consider using gpg2.

RETURN VALUE

       The program returns 0 if everything was fine, 1 if at least a signature
       was bad, and other error codes for fatal errors.

WARNINGS

       Use a *good* password for your user account and a *good* passphrase  to
       protect  your  secret  key.  This passphrase is the weakest part of the
       whole system. Programs to do dictionary attacks on your secret  keyring
       are  very  easy  to  write  and  so you should protect your "~/.gnupg/"
       directory very well.

       Keep in mind that, if this program is used over a network (telnet),  it
       is *very* easy to spy out your passphrase!

       If  you  are  going  to  verify detached signatures, make sure that the
       program knows about it; either give both filenames on the command  line
       or use '-'’ to specify STDIN.

INTEROPERABILITY

       GnuPG  tries  to  be  a  very  flexible  implementation  of the OpenPGP
       standard. In particular, GnuPG implements many of the optional parts of
       the  standard,  such  as  the  SHA-512  hash,  and  the  ZLIB and BZIP2
       compression algorithms. It is  important  to  be  aware  that  not  all
       OpenPGP  programs  implement  these  optional  algorithms  and  that by
       forcing their use via the --cipher-algo, --digest-algo,  --cert-digest-
       algo,  or  --compress-algo options in GnuPG, it is possible to create a
       perfectly valid OpenPGP message, but one that cannot  be  read  by  the
       intended recipient.

       There  are dozens of variations of OpenPGP programs available, and each
       supports a slightly different subset of these optional algorithms.  For
       example,  until  recently,  no  (unhacked) version of PGP supported the
       BLOWFISH cipher algorithm. A message using BLOWFISH simply could not be
       read  by  a  PGP  user.  By  default,  GnuPG  uses the standard OpenPGP
       preferences system that will always  do  the  right  thing  and  create
       messages that are usable by all recipients, regardless of which OpenPGP
       program they use. Only override this safe default if  you  really  know
       what you are doing.

       If you absolutely must override the safe default, or if the preferences
       on a given key are invalid for some reason,  you  are  far  better  off
       using  the --pgp6, --pgp7, or --pgp8 options. These options are safe as
       they do not force any particular algorithms in  violation  of  OpenPGP,
       but rather reduce the available algorithms to a "PGP-safe" list.

COMMANDS

       Commands  are  not  distinguished from options except for the fact that
       only one command is allowed.

       gpg may be run with no commands,  in  which  case  it  will  perform  a
       reasonable  action  depending  on the type of file it is given as input
       (an encrypted message is decrypted, a signature  is  verified,  a  file
       containing keys is listed).

       Please remember that option as well as command parsing stops as soon as
       a non-option is encountered, you can explicitly stop parsing  by  using
       the special option --.

   Commands not specific to the function

       --version
              Print  the program version and licensing information.  Note that
              you cannot abbreviate this command.

       --help

       -h     Print a usage message summarizing the most useful  command  line
              options.  Note that you cannot abbreviate this command.

       --warranty
              Print warranty information.

       --dump-options
              Print  a  list of all available options and commands.  Note that
              you cannot abbreviate this command.

   Commands to select the type of operation

       --sign

       -s     Make a signature. This command may be  combined  with  --encrypt
              (for  a signed and encrypted message), --symmetric (for a signed
              and  symmetrically  encrypted   message),   or   --encrypt   and
              --symmetric together (for a signed message that may be decrypted
              via a secret key or a passphrase).   The  key  to  be  used  for
              signing is chosen by default or can be set with the --local-user
              and --default-key options.

       --clearsign
              Make a clear text  signature.   The  content  in  a  clear  text
              signature  is  readable  without  any  special software. OpenPGP
              software is only needed to verify  the  signature.   Clear  text
              signatures   may  modify  end-of-line  whitespace  for  platform
              independence and are not intended to be reversible.  The key  to
              be  used for signing is chosen by default or can be set with the
              --local-user and --default-key options.

       --detach-sign

       -b     Make a detached signature.

       --encrypt

       -e     Encrypt data. This option may be combined  with  --sign  (for  a
              signed  and  encrypted message), --symmetric (for a message that
              may be decrypted via a secret key or a  passphrase),  or  --sign
              and  --symmetric  together  (for  a  signed  message that may be
              decrypted via a secret key or a passphrase).

       --symmetric

       -c     Encrypt with a symmetric cipher using a passphrase. The  default
              symmetric  cipher  used  is  CAST5,  but  may be chosen with the
              --cipher-algo option. This option may be  combined  with  --sign
              (for  a  signed  and symmetrically encrypted message), --encrypt
              (for a message that may be decrypted  via  a  secret  key  or  a
              passphrase),  or  --sign  and  --encrypt  together (for a signed
              message that may be decrypted via a secret key or a passphrase).

       --store
              Store only (make a simple RFC1991 literal data packet).

       --decrypt

       -d     Decrypt  the file given on the command line (or STDIN if no file
              is specified) and write it to STDOUT (or the file specified with
              --output).  If  the  decrypted  file is signed, the signature is
              also verified. This command differs from the default  operation,
              as it never writes to the filename which is included in the file
              and it  rejects  files  which  don’t  begin  with  an  encrypted
              message.

       --verify
              Assume  that  the  first argument is a signed file or a detached
              signature and verify it without generating any output.  With  no
              arguments,  the  signature  packet is read from STDIN. If only a
              sigfile is given, it may be a complete signature or  a  detached
              signature,  in which case the signed stuff is expected in a file
              without the ".sig"  or  ".asc"  extension.   With  more  than  1
              argument,  the  first  should  be  a  detached signature and the
              remaining files are the signed stuff. To read the  signed  stuff
              from  STDIN,  use  '-'’  as  the  second filename.  For security
              reasons a detached signature cannot  read  the  signed  material
              from STDIN without denoting it in the above way.

       --multifile
              This  modifies  certain  other commands to accept multiple files
              for processing on the command line or read from STDIN with  each
              filename  on  a  separate line. This allows for many files to be
              processed at once. --multifile may currently be used along  with
              --verify,   --encrypt,  and  --decrypt.  Note  that  --multifile
              --verify may not be used with detached signatures.

       --verify-files
              Identical to --multifile --verify.

       --encrypt-files
              Identical to --multifile --encrypt.

       --decrypt-files
              Identical to --multifile --decrypt.

       --list-keys

       -k

       --list-public-keys
              List all keys from the public keyrings, or just the  keys  given
              on  the command line.  -k is slightly different from --list-keys
              in that it allows only for one argument  and  takes  the  second
              argument  as  the  keyring  to search.  This is for command line
              compatibility with PGP 2 and has been removed in gpg2.

              Avoid using the output of  this  command  in  scripts  or  other
              programs as it is likely to change as GnuPG changes. See --with-
              colons for a  machine-parseable  key  listing  command  that  is
              appropriate for use in scripts and other programs.

       --list-secret-keys

       -K     List  all  keys from the secret keyrings, or just the ones given
              on the command line. A # after the letters sec  means  that  the
              secret  key  is  not  usable (for example, if it was created via
              --export-secret-subkeys).

       --list-sigs
              Same as --list-keys, but the signatures are listed too.

              For each signature listed, there are several  flags  in  between
              the "sig" tag and keyid. These flags give additional information
              about each signature. From left to right, they are  the  numbers
              1-3  for certificate check level (see --ask-cert-level), "L" for
              a local or non-exportable signature (see --lsign-key), "R" for a
              nonRevocable  signature  (see  the --edit-key command "nrsign"),
              "P" for a signature that contains  a  policy  URL  (see  --cert-
              policy-url),  "N"  for a signature that contains a notation (see
              --cert-notation), "X" for an eXpired signature (see  --ask-cert-
              expire), and the numbers 1-9 or "T" for 10 and above to indicate
              trust signature levels (see the --edit-key command "tsign").

       --check-sigs
              Same as --list-sigs, but the signatures are verified.  Note that
              for  performance  reasons the revocation status of a signing key
              is not shown.

              The status of the verification is indicated by a  flag  directly
              following  the  "sig"  tag  (and thus before the flags described
              above for --list-sigs).  A "!" indicates that the signature  has
              been  successfully verified, a "-" denotes a bad signature and a
              "%" is used if an error occurred while  checking  the  signature
              (e.g. a non supported algorithm).

       --fingerprint
              List   all  keys  (or  the  specified  ones)  along  with  their
              fingerprints. This is the same output as  --list-keys  but  with
              the  additional  output of a line with the fingerprint. May also
              be combined with --list-sigs or --check-sigs.  If  this  command
              is  given  twice,  the  fingerprints  of  all secondary keys are
              listed too.

       --list-packets
              List only the sequence of packets. This  is  mainly  useful  for
              debugging.

       --card-edit
              Present  a  menu to work with a smartcard. The subcommand "help"
              provides an overview  on  available  commands.  For  a  detailed
              description,     please     see     the     Card     HOWTO    at
              http://www.gnupg.org/documentation/howtos.html#GnuPG-cardHOWTO .

       --card-status
              Show the content of the smart card.

       --change-pin
              Present  a  menu  to allow changing the PIN of a smartcard. This
              functionality is also available as the subcommand "passwd"  with
              the --card-edit command.

       --delete-key name
              Remove  key  from the public keyring. In batch mode either --yes
              is required or the key must be specified by fingerprint. This is
              a safeguard against accidental deletion of multiple keys.

       --delete-secret-key name
              Remove key from the secret and public keyring. In batch mode the
              key must be specified by fingerprint.

       --delete-secret-and-public-key name
              Same as --delete-key, but if a secret key  exists,  it  will  be
              removed  first.  In  batch  mode  the  key  must be specified by
              fingerprint.

       --export
              Either export all keys from all keyrings (default  keyrings  and
              those  registered via option --keyring), or if at least one name
              is given, those of the given name. The new keyring is written to
              STDOUT  or  to the file given with option --output. Use together
              with --armor to mail those keys.

       --send-keys key IDs
              Similar  to  --export  but  sends  the  keys  to  a   keyserver.
              Fingerprints  may be used instead of key IDs. Option --keyserver
              must be used to give the name of this keyserver. Don’t send your
              complete keyring to a keyserver --- select only those keys which
              are new or changed by you.  If no key IDs are  given,  gpg  does
              nothing.

       --export-secret-keys

       --export-secret-subkeys
              Same  as --export, but exports the secret keys instead.  This is
              normally not very useful and a security risk.  The  second  form
              of  the  command  has  the special property to render the secret
              part of the primary key useless; this  is  a  GNU  extension  to
              OpenPGP  and  other  implementations  can  not  be  expected  to
              successfully import such a key.   See  the  option  --simple-sk-
              checksum  if  you  want  to  import such an exported key with an
              older OpenPGP implementation.

       --import

       --fast-import
              Import/merge keys. This adds the given keys to the keyring.  The
              fast version is currently just a synonym.

              There  are  a  few  other options which control how this command
              works.  Most notable here  is  the  --import-options  merge-only
              option  which does not insert new keys but does only the merging
              of new signatures, user-IDs and subkeys.

       --recv-keys key IDs
              Import the keys with the given key IDs from a keyserver.  Option
              --keyserver must be used to give the name of this keyserver.

       --refresh-keys
              Request  updates from a keyserver for keys that already exist on
              the local keyring. This is useful for updating a  key  with  the
              latest signatures, user IDs, etc. Calling this with no arguments
              will refresh the entire keyring. Option --keyserver must be used
              to  give the name of the keyserver for all keys that do not have
              preferred  keyservers  set   (see   --keyserver-options   honor-
              keyserver-url).

       --search-keys names
              Search  the  keyserver for the given names. Multiple names given
              here will be joined together to create the search string for the
              keyserver.   Option --keyserver must be used to give the name of
              this  keyserver.   Keyservers  that  support  different   search
              methods  allow  using  the syntax specified in "How to specify a
              user ID" below. Note  that  different  keyserver  types  support
              different search methods. Currently only LDAP supports them all.

       --fetch-keys URIs
              Retrieve keys located at the specified URIs. Note that different
              installations  of  GnuPG  may support different protocols (HTTP,
              FTP, LDAP, etc.)

       --update-trustdb
              Do trust database maintenance. This command  iterates  over  all
              keys and builds the Web of Trust. This is an interactive command
              because it may have to ask for the "ownertrust" values for keys.
              The  user  has  to  give an estimation of how far she trusts the
              owner of the displayed key to  correctly  certify  (sign)  other
              keys. GnuPG only asks for the ownertrust value if it has not yet
              been assigned to a key. Using the --edit-key menu, the  assigned
              value can be changed at any time.

       --check-trustdb
              Do  trust  database  maintenance  without user interaction. From
              time to time the trust database must be updated so that  expired
              keys or signatures and the resulting changes in the Web of Trust
              can be tracked. Normally, GnuPG  will  calculate  when  this  is
              required  and do it automatically unless --no-auto-check-trustdb
              is set. This command can be used to force a trust database check
              at  any  time.  The processing is identical to that of --update-
              trustdb but it skips keys with a not yet defined "ownertrust".

              For use with cron jobs, this command can be used  together  with
              --batch in which case the trust database check is done only if a
              check is needed. To force a run  even  in  batch  mode  add  the
              option --yes.

       --export-ownertrust
              Send  the ownertrust values to STDOUT. This is useful for backup
              purposes as these values are the only ones which  can’t  be  re-
              created from a corrupted trustdb.  Example:
                  gpg --export-ownertrust > otrust.txt

       --import-ownertrust
              Update  the  trustdb  with the ownertrust values stored in files
              (or STDIN if not given); existing values  will  be  overwritten.
              In  case  of a severely damaged trustdb and if you have a recent
              backup of the ownertrust values (e.g. in the file  ‘otrust.txt’,
              you may re-create the trustdb using these commands:
                  cd ~/.gnupg
                  rm trustdb.gpg
                  gpg --import-ownertrust < otrust.txt

       --rebuild-keydb-caches
              When updating from version 1.0.6 to 1.0.7 this command should be
              used to create signature caches in  the  keyring.  It  might  be
              handy in other situations too.

       --print-md algo

       --print-mds
              Print  message  digest  of algorithm ALGO for all given files or
              STDIN.  With the second form  (or  a  deprecated  "*"  as  algo)
              digests for all available algorithms are printed.

       --gen-random 0|1|2
              Emit  count random bytes of the given quality level. If count is
              not given or zero, an endless sequence of random bytes  will  be
              emitted.   PLEASE,  don’t  use this command unless you know what
              you are doing; it may remove precious entropy from the system!

       --gen-prime mode bits
              Use the source, Luke :-). The output format is still subject  to
              change.

       --enarmor

       --dearmor
              Pack  or  unpack  an  arbitrary input into/from an OpenPGP ASCII
              armor.  This is a GnuPG extension to OpenPGP and in general  not
              very useful.

   How to manage your keys

       This section explains the main commands for key management

       --gen-key
              Generate  a  new  key  pair.  This command is normally only used
              interactively.

              There is an experimental feature which allows you to create keys
              in  batch  mode.  See  the  file  ‘doc/DETAILS’  in  the  source
              distribution on how to use this.

       --gen-revoke name
              Generate a revocation  certificate  for  the  complete  key.  To
              revoke a subkey or a signature, use the --edit command.

       --desig-revoke name
              Generate  a  designated  revocation  certificate for a key. This
              allows a user (with the permission of the keyholder)  to  revoke
              someone else’s key.

       --edit-key
              Present  a  menu  which  enables  you  to  do  most  of  the key
              management related tasks.  It expects the specification of a key
              on the command line.

              uid n  Toggle  selection of user ID or photographic user ID with
                     index n.  Use 0 to deselect all.

              key n  Toggle selection of  subkey  with  index  n.   Use  0  to
                     deselect all.

              sign   Make  a  signature  on key of user name If the key is not
                     yet signed by the default user (or the users  given  with
                     -u),  the  program  displays  the  information of the key
                     again, together with its fingerprint and asks whether  it
                     should be signed. This question is repeated for all users
                     specified with -u.

              lsign  Same as "sign"  but  the  signature  is  marked  as  non-
                     exportable  and  will  therefore never be used by others.
                     This may be used to make keys valid  only  in  the  local
                     environment.

              nrsign Same  as  "sign"  but  the  signature  is  marked as non-
                     revocable and can therefore never be revoked.

              tsign  Make a trust signature. This is a signature that combines
                     the  notions of certification (like a regular signature),
                     and trust (like the "trust"  command).  It  is  generally
                     only useful in distinct communities or groups.

              Note  that  "l"  (for  local  /  non-exportable), "nr" (for non-
              revocable, and "t" (for trust) may be freely mixed and  prefixed
              to "sign" to create a signature of any type desired.

              delsig Delete  a  signature.  Note  that  it  is not possible to
                     retract a signature, once it has been send to the  public
                     (i.e.  to  a  keyserver).   In  that  case you better use
                     revsig.

              revsig Revoke a signature. For every signature  which  has  been
                     generated by one of the secret keys, GnuPG asks whether a
                     revocation certificate should be generated.

              check  Check the signatures on all selected user IDs.

              adduid Create an additional user ID.

              addphoto
                     Create a photographic user ID. This  will  prompt  for  a
                     JPEG  file  that  will be embedded into the user ID. Note
                     that a very large JPEG will make for a  very  large  key.
                     Also  note  that  some  programs  will  display your JPEG
                     unchanged (GnuPG), and some programs will scale it to fit
                     in a dialog box (PGP).

              showphoto
                     Display the selected photographic user ID.

              deluid Delete  a  user ID or photographic user ID.  Note that it
                     is not possible to retract a user id, once  it  has  been
                     send  to  the public (i.e. to a keyserver).  In that case
                     you better use revuid.

              revuid Revoke a user ID or photographic user ID.

              primary
                     Flag the current user id as the primary one, removes  the
                     primary user id flag from all other user ids and sets the
                     timestamp of  all  affected  self-signatures  one  second
                     ahead. Note that setting a photo user ID as primary makes
                     it primary over other  photo  user  IDs,  and  setting  a
                     regular  user  ID  as primary makes it primary over other
                     regular user IDs.

              keyserver
                     Set a preferred keyserver for the specified  user  ID(s).
                     This allows other users to know where you prefer they get
                     your key from. See  --keyserver-options  honor-keyserver-
                     url  for  more  on  how  this  works.  Setting a value of
                     "none" removes an existing preferred keyserver.

              notation
                     Set a name=value notation for the specified  user  ID(s).
                     See --cert-notation for more on how this works. Setting a
                     value of "none" removes all notations, setting a notation
                     prefixed with a minus sign (-) removes that notation, and
                     setting a notation name  (without  the  =value)  prefixed
                     with a minus sign removes all notations with that name.

              pref   List  preferences  from  the selected user ID. This shows
                     the actual preferences,  without  including  any  implied
                     preferences.

              showpref
                     More  verbose  preferences  listing for the selected user
                     ID. This shows the preferences in effect by including the
                     implied preferences of 3DES (cipher), SHA-1 (digest), and
                     Uncompressed  (compression)  if  they  are  not   already
                     included   in  the  preference  list.  In  addition,  the
                     preferred keyserver and signature notations (if any)  are
                     shown.

              setpref string
                     Set the list of user ID preferences to string for all (or
                     just the selected) user  IDs.  Calling  setpref  with  no
                     arguments sets the preference list to the default (either
                     built-in  or  set  via  --default-preference-list),   and
                     calling setpref with "none" as the argument sets an empty
                     preference list. Use gpg  --version  to  get  a  list  of
                     available  algorithms. Note that while you can change the
                     preferences on an attribute user  ID  (aka  "photo  ID"),
                     GnuPG  does  not  select  keys  via attribute user IDs so
                     these preferences will not be used by GnuPG.

                     When setting preferences, you should list the  algorithms
                     in the order which you’d like to see them used by someone
                     else when encrypting a message to your key.  If you don’t
                     include  3DES, it will be automatically added at the end.
                     Note that there are many factors that go into choosing an
                     algorithm  (for  example,  your  key  may not be the only
                     recipient), and so the remote OpenPGP  application  being
                     used  to  send  to  you  may or may not follow your exact
                     chosen order for a given message.  It will, however, only
                     choose  an  algorithm  that  is present on the preference
                     list   of   every   recipient   key.    See   also    the
                     INTEROPERABILITY  WITH  OTHER  OPENPGP  PROGRAMS  section
                     below.

              addkey Add a subkey to this key.

              addcardkey
                     Generate a subkey on a card and add it to this key.

              keytocard
                     Transfer the selected secret subkey (or the  primary  key
                     if  no  subkey  has  been  selected)  to a smartcard. The
                     secret key in the keyring will be replaced by a  stub  if
                     the  key could be stored successfully on the card and you
                     use the save command later. Only certain key types may be
                     transferred  to the card. A sub menu allows you to select
                     on what card to store  the  key.  Note  that  it  is  not
                     possible to get that key back from the card - if the card
                     gets broken your secret key will be lost unless you  have
                     a backup somewhere.

              bkuptocard file
                     Restore  the  given  file  to a card. This command may be
                     used to restore a backup key (as  generated  during  card
                     initialization)  to  a new card. In almost all cases this
                     will be the encryption key. You should use  this  command
                     only with the corresponding public key and make sure that
                     the file given  as  argument  is  indeed  the  backup  to
                     restore.   You   should  then  select  2  to  restore  as
                     encryption key.  You will first be  asked  to  enter  the
                     passphrase  of  the backup key and then for the Admin PIN
                     of the card.

              delkey Remove a subkey (secondart key).  Note  that  it  is  not
                     possible  to  retract  a subkey, once it has been send to
                     the public (i.e. to  a  keyserver).   In  that  case  you
                     better use revkey.

              revkey Revoke a subkey.

              expire Change  the key or subkey expiration time. If a subkey is
                     selected, the expiration time  of  this  subkey  will  be
                     changed.  With  no  selection,  the key expiration of the
                     primary key is changed.

              trust  Change the owner trust value for the  key.  This  updates
                     the trust-db immediately and no save is required.

              disable

              enable Disable  or  enable an entire key. A disabled key can not
                     normally be used for encryption.

              addrevoker
                     Add a designated revoker  to  the  key.  This  takes  one
                     optional  argument:  "sensitive". If a designated revoker
                     is marked as  sensitive,  it  will  not  be  exported  by
                     default (see export-options).

              passwd Change the passphrase of the secret key.

              toggle Toggle between public and secret key listing.

              clean  Compact  (by  removing all signatures except the selfsig)
                     any user ID that is no longer usable  (e.g.  revoked,  or
                     expired). Then, remove any signatures that are not usable
                     by the trust calculations.   Specifically,  this  removes
                     any  signature that does not validate, any signature that
                     is superseded by a later signature,  revoked  signatures,
                     and signatures issued by keys that are not present on the
                     keyring.

              minimize
                     Make the key as  small  as  possible.  This  removes  all
                     signatures  from  each user ID except for the most recent
                     self-signature.

              cross-certify
                     Add cross-certification  signatures  to  signing  subkeys
                     that  may  not  currently  have them. Cross-certification
                     signatures  protect  against  a  subtle  attack   against
                     signing  subkeys. See --require-cross-certification.  All
                     new keys generated have this  signature  by  default,  so
                     this  option  is  only  useful  to bring older keys up to
                     date.

              save   Save all changes to the key rings and quit.

              quit   Quit the program without updating the key rings.

              The listing shows you the key with its secondary  keys  and  all
              user  ids.  Selected  keys  or  user  ids  are  indicated  by an
              asterisk. The trust value is displayed with the primary key: the
              first  is  the  assigned  owner  trust  and  the  second  is the
              calculated trust value. Letters are used for the values:

              -      No ownertrust assigned / not yet calculated.

              e      Trust calculation has failed; probably due to an  expired
                     key.

              q      Not enough information for calculation.

              n      Never trust this key.

              m      Marginally trusted.

              f      Fully trusted.

              u      Ultimately trusted.

       --sign-key name
              Signs  a  public  key  with  your secret key. This is a shortcut
              version of the subcommand "sign" from --edit.

       --lsign-key name
              Signs a public key with your secret key but  marks  it  as  non-
              exportable. This is a shortcut version of the subcommand "lsign"
              from --edit-key.

OPTIONS

       gpg comes features a bunch of options to control  the  exact  behaviour
       and to change the default configuration.

       Long    options    can   be   put   in   an   options   file   (default
       "~/.gnupg/gpg.conf"). Short option names will not work -  for  example,
       "armor"  is  a  valid option for the options file, while "a" is not. Do
       not write the 2 dashes, but simply the  name  of  the  option  and  any
       required  arguments.  Lines  with  a hash (’#’) as the first non-white-
       space character are ignored. Commands may be put in this file too,  but
       that  is not generally useful as the command will execute automatically
       with every execution of gpg.

       Please remember that option parsing stops as soon as  a  non-option  is
       encountered,  you  can  explicitly  stop  parsing  by using the special
       option --.

   How to change the configuration

       These options are used to change  the  configuration  and  are  usually
       found in the option file.

       --default-key name
              Use  name as the default key to sign with. If this option is not
              used, the default key is the  first  key  found  in  the  secret
              keyring.  Note that -u or --local-user overrides this option.

       --default-recipient name
              Use  name as default recipient if option --recipient is not used
              and don’t ask if this is a valid one. name must be non-empty.

       --default-recipient-self
              Use the default key as default recipient if  option  --recipient
              is  not  used  and don’t ask if this is a valid one. The default
              key is the first one from the secret keyring or the one set with
              --default-key.

       --no-default-recipient
              Reset --default-recipient and --default-recipient-self.

       -v, --verbose
              Give  more  information  during  processing.  If used twice, the
              input data is listed in detail.

       --no-verbose
              Reset verbose level to 0.

       -q, --quiet
              Try to be as quiet as possible.

       --batch

       --no-batch
              Use batch mode.  Never ask, do not allow  interactive  commands.
              --no-batch disables this option.  Note that even with a filename
              given on the command line, gpg might still  need  to  read  from
              STDIN (in particular if gpg figures that the input is a detached
              signature and no data file has been specified).  Thus if you  do
              not  want  to  feed  data via STDIN, you should connect STDIN to
              ‘/dev/null’.

       --no-tty
              Make sure that the TTY (terminal) is never used for any  output.
              This  option  is  needed  in  some cases because GnuPG sometimes
              prints warnings to the TTY even if --batch is used.

       --yes  Assume "yes" on most questions.

       --no   Assume "no" on most questions.

       --list-options parameters
              This is a space or comma delimited  string  that  gives  options
              used  when  listing  keys  and signatures (that is, --list-keys,
              --list-sigs,  --list-public-keys,  --list-secret-keys,  and  the
              --edit-key  functions).   Options  can  be  prepended with a no-
              (after the two  dashes)  to  give  the  opposite  meaning.   The
              options are:

              show-photos
                     Causes  --list-keys, --list-sigs, --list-public-keys, and
                     --list-secret-keys to display any photo IDs  attached  to
                     the key.  Defaults to no. See also --photo-viewer.

              show-policy-urls
                     Show  policy  URLs  in  the  --list-sigs  or --check-sigs
                     listings.  Defaults to no.

              show-notations

              show-std-notations

              show-user-notations
                     Show  all,  IETF  standard,  or  user-defined   signature
                     notations  in  the  --list-sigs or --check-sigs listings.
                     Defaults to no.

              show-keyserver-urls

                     Show any preferred keyserver URL in  the  --list-sigs  or
                     --check-sigs listings. Defaults to no.

              show-uid-validity
                     Display  the  calculated  validity of user IDs during key
                     listings.  Defaults to no.

              show-unusable-uids
                     Show revoked  and  expired  user  IDs  in  key  listings.
                     Defaults to no.

              show-unusable-subkeys
                     Show   revoked  and  expired  subkeys  in  key  listings.
                     Defaults to no.

              show-keyring
                     Display the keyring name at the head of key  listings  to
                     show  which  keyring  a given key resides on. Defaults to
                     no.

              show-sig-expire
                     Show signature expiration dates (if any)  during  --list-
                     sigs or --check-sigs listings. Defaults to no.

              show-sig-subpackets
                     Include  signature  subpackets  in  the key listing. This
                     option  can  take  an  optional  argument  list  of   the
                     subpackets  to  list.  If no argument is passed, list all
                     subpackets.  Defaults  to  no.  This   option   is   only
                     meaningful  when  using  --with-colons along with --list-
                     sigs or --check-sigs.

       --verify-options parameters
              This is a space or comma delimited  string  that  gives  options
              used  when verifying signatures. Options can be prepended with a
              ‘no-’ to give the opposite meaning. The options are:

              show-photos
                     Display any photo IDs present on the key that issued  the
                     signature.  Defaults to no. See also --photo-viewer.

              show-policy-urls
                     Show   policy  URLs  in  the  signature  being  verified.
                     Defaults to no.

              show-notations

              show-std-notations

              show-user-notations
                     Show  all,  IETF  standard,  or  user-defined   signature
                     notations  in  the  signature being verified. Defaults to
                     IETF standard.

              show-keyserver-urls
                     Show any preferred keyserver URL in the  signature  being
                     verified.  Defaults to no.

              show-uid-validity
                     Display  the  calculated  validity of the user IDs on the
                     key that issued the signature. Defaults to no.

              show-unusable-uids
                     Show  revoked  and  expired  user  IDs  during  signature
                     verification.  Defaults to no.

              show-primary-uid-only
                     Show   only   the   primary   user  ID  during  signature
                     verification.  That is all the AKA lines as well as photo
                     Ids are not shown with the signature verification status.

              pka-lookups
                     Enable PKA lookups to verify sender addresses. Note  that
                     PKA  is  based  on  DNS,  and so enabling this option may
                     disclose information on  when  and  what  signatures  are
                     verified or to whom data is encrypted. This is similar to
                     the  "web  bug"  described  for   the   auto-key-retrieve
                     feature.

              pka-trust-increase
                     Raise  the  trust in a signature to full if the signature
                     passes PKA validation. This option is only meaningful  if
                     pka-lookups is set.

       --enable-dsa2

       --disable-dsa2
              Enable hash truncation for all DSA keys even for old DSA Keys up
              to 1024 bit.  This is also the  default  with  --openpgp.   Note
              that  older  versions  of GnuPG also required this flag to allow
              the generation of DSA larger than 1024 bit.

       --photo-viewer string
              This is the command line that should be run to view a photo  ID.
              "%i"  will  be expanded to a filename containing the photo. "%I"
              does the same, except the file will  not  be  deleted  once  the
              viewer exits.  Other flags are "%k" for the key ID, "%K" for the
              long key  ID,  "%f"  for  the  key  fingerprint,  "%t"  for  the
              extension of the image type (e.g. "jpg"), "%T" for the MIME type
              of the image (e.g. "image/jpeg"), and "%%" for an actual percent
              sign.  If  neither  %i or %I are present, then the photo will be
              supplied to the viewer on standard input.

              The default viewer is "xloadimage  -fork  -quiet  -title  ’KeyID
              0x%k’  STDIN".  Note  that  if  your image viewer program is not
              secure, then executing it from GnuPG does not make it secure.

       --exec-path string
              Sets a list of directories  to  search  for  photo  viewers  and
              keyserver  helpers.  If  not provided, keyserver helpers use the
              compiled-in default directory, and photo viewers use  the  $PATH
              environment  variable.   Note,  that on W32 system this value is
              ignored when searching for keyserver helpers.

       --keyring file
              Add file to the current list of keyrings. If file begins with  a
              tilde and a slash, these are replaced by the $HOME directory. If
              the filename does not contain a slash, it is assumed  to  be  in
              the  GnuPG home directory ("~/.gnupg" if --homedir or $GNUPGHOME
              is not used).

              Note that this adds a keyring to the current list. If the intent
              is  to use the specified keyring alone, use --keyring along with
              --no-default-keyring.

       --secret-keyring file
              Same as --keyring but for the secret keyrings.

       --primary-keyring file
              Designate file as the primary public keyring.  This  means  that
              newly imported keys (via --import or keyserver --recv-from) will
              go to this keyring.

       --trustdb-name file
              Use file instead of the default trustdb. If file begins  with  a
              tilde and a slash, these are replaced by the $HOME directory. If
              the filename does not contain a slash, it is assumed  to  be  in
              the  GnuPG home directory (‘~/.gnupg’ if --homedir or $GNUPGHOME
              is not used).

       --homedir dir
              Set the name of the home directory to dir. If this option is not
              used,  the  home  directory  defaults to ‘~/.gnupg’.  It is only
              recognized when given on the command line.   It  also  overrides
              any  home  directory  stated  through  the  environment variable
              ‘GNUPGHOME’ or (on W32 systems) by means of the  Registry  entry
              HKCU\Software\GNU\GnuPG:HomeDir.

       --pcsc-driver file
              Use  file to access the smartcard reader. The current default is
              ‘libpcsclite.so.1’      for      GLIBC      based       systems,
              ‘/System/Library/Frameworks/PCSC.framework/PCSC’  for  MAC OS X,
              ‘winscard.dll’  for  Windows  and  ‘libpcsclite.so’  for   other
              systems.

       --disable-ccid
              Disable  the integrated support for CCID compliant readers. This
              allows to fall back to one of the  other  drivers  even  if  the
              internal  CCID  driver  can  handle  the reader. Note, that CCID
              support is only available if libusb was available at build time.

       --reader-port number_or_string
              This  option  may  be  used  to  specify  the  port  of the card
              terminal. A value of 0 refers to the first  serial  device;  add
              32768  to  access  USB  devices. The default is 32768 (first USB
              device). PC/SC or CCID readers might need a string here; run the
              program  in verbose mode to get a list of available readers. The
              default is then the first reader found.

       --display-charset name
              Set the name of the  native  character  set.  This  is  used  to
              convert  some  informational strings like user IDs to the proper
              UTF-8 encoding.  Note that this  has  nothing  to  do  with  the
              character  set of data to be encrypted or signed; GnuPG does not
              recode user-supplied data. If  this  option  is  not  used,  the
              default  character  set is determined from the current locale. A
              verbosity level of 3 shows the chosen  set.   Valid  values  for
              name are:

              iso-8859-1
                     This is the Latin 1 set.

              iso-8859-2
                     The Latin 2 set.

              iso-8859-15
                     This is currently an alias for the Latin 1 set.

              koi8-r The usual Russian set (rfc1489).

              utf-8  Bypass  all  translations  and  assume  that  the OS uses
                     native UTF-8 encoding.

       --utf8-strings

       --no-utf8-strings
              Assume that command line arguments are given  as  UTF8  strings.
              The  default (--no-utf8-strings) is to assume that arguments are
              encoded in the character set as specified by  --display-charset.
              These  options  affect all following arguments. Both options may
              be used multiple times.

       --options file
              Read options from file and do not try  to  read  them  from  the
              default options file in the homedir (see --homedir). This option
              is ignored if used in an options file.

       --no-options
              Shortcut for --options /dev/null. This option is detected before
              an  attempt to open an option file.  Using this option will also
              prevent the creation of a ‘~/.gnupg’ homedir.

       -z n

       --compress-level n

       --bzip2-compress-level n
              Set compression level to n for  the  ZIP  and  ZLIB  compression
              algorithms.  The default is to use the default compression level
              of  zlib   (normally   6).   --bzip2-compress-level   sets   the
              compression   level   for   the   BZIP2   compression  algorithm
              (defaulting to 6 as well).  This  is  a  different  option  from
              --compress-level since BZIP2 uses a significant amount of memory
              for each additional compression level.  -z sets both. A value of
              0 for n disables compression.

       --bzip2-decompress-lowmem
              Use a different decompression method for BZIP2 compressed files.
              This alternate method uses a bit more than half the memory,  but
              also  runs  at  half the speed. This is useful under extreme low
              memory circumstances when the file was originally compressed  at
              a high --bzip2-compress-level.

       --mangle-dos-filenames

       --no-mangle-dos-filenames
              Older  version of Windows cannot handle filenames with more than
              one dot. --mangle-dos-filenames causes GnuPG to replace  (rather
              than  add  to) the extension of an output filename to avoid this
              problem. This option is off by default and has no effect on non-
              Windows platforms.

       --ask-cert-level

       --no-ask-cert-level
              When  making  a key signature, prompt for a certification level.
              If this option is not specified, the certification level used is
              set   via  --default-cert-level.  See  --default-cert-level  for
              information on the specific levels and how they are used.  --no-
              ask-cert-level disables this option. This option defaults to no.

       --default-cert-level n
              The default to use for the check level when signing a key.

              0 means you make no particular claim as  to  how  carefully  you
              verified the key.

              1 means you believe the key is owned by the person who claims to
              own it but you could not, or did not verify the key at all. This
              is  useful  for a "persona" verification, where you sign the key
              of a pseudonymous user.

              2 means you did casual verification of  the  key.  For  example,
              this  could  mean that you verified that the key fingerprint and
              checked the user ID on the key against a photo ID.

              3 means you did extensive verification of the key. For  example,
              this  could  mean that you verified the key fingerprint with the
              owner of the key in person, and that you checked, by means of  a
              hard to forge document with a photo ID (such as a passport) that
              the name of the key owner matches the name in the user ID on the
              key,  and  finally that you verified (by exchange of email) that
              the email address on the key belongs to the key owner.

              Note that the examples given above for levels 2 and 3  are  just
              that:  examples. In the end, it is up to you to decide just what
              "casual" and "extensive" mean to you.

              This option defaults to 0 (no particular claim).

       --min-cert-level
              When building the trust database, treat any  signatures  with  a
              certification  level below this as invalid. Defaults to 2, which
              disregards level 1 signatures. Note that level 0 "no  particular
              claim" signatures are always accepted.

       --trusted-key long key ID
              Assume  that  the specified key (which must be given as a full 8
              byte key ID) is as trustworthy as one of your own  secret  keys.
              This option is useful if you don’t want to keep your secret keys
              (or one of them) online but still want to be able to  check  the
              validity of a given recipient’s or signator’s key.

       --trust-model pgp|classic|direct|always|auto
              Set what trust model GnuPG should follow. The models are:

              pgp    This  is  the Web of Trust combined with trust signatures
                     as used in PGP 5.x and later. This is the  default  trust
                     model when creating a new trust database.

              classic
                     This  is the standard Web of Trust as used in PGP 2.x and
                     earlier.

              direct Key  validity  is  set  directly  by  the  user  and  not
                     calculated via the Web of Trust.

              always Skip  key validation and assume that used keys are always
                     fully trusted. You generally won’t use  this  unless  you
                     are  using  some  external validation scheme. This option
                     also  suppresses  the  "[uncertain]"  tag  printed   with
                     signature  checks when there is no evidence that the user
                     ID is bound to the key.

              auto   Select the trust model depending on whatever the internal
                     trust  database says. This is the default model if such a
                     database already exists.

       --auto-key-locate parameters

       --no-auto-key-locate
              GnuPG can automatically locate and retrieve keys as needed using
              this  option.  This  happens when encrypting to an email address
              (in   the   "user@example.com"   form),   and   there   are   no
              user@example.com  keys  on the local keyring.  This option takes
              any number of the following mechanisms, in the order they are to
              be tried:

              cert   Locate a key using DNS CERT, as specified in rfc4398.

              pka    Locate a key using DNS PKA.

              ldap   Using DNS Service Discovery, check the domain in question
                     for any LDAP keyservers to use.  If this  fails,  attempt
                     to  locate  the  key  using  the  PGP Universal method of
                     checking 'ldap://keys.(thedomain)'’.

              keyserver
                     Locate a key using whatever keyserver  is  defined  using
                     the --keyserver option.

              keyserver-URL
                     In  addition,  a keyserver URL as used in the --keyserver
                     option  may  be  used  here  to  query  that   particular
                     keyserver.

              local  Locate  the key using the local keyrings.  This mechanism
                     allows to select the order a local key  lookup  is  done.
                     Thus  using  '--auto-key-locate  local'’  is identical to
                     --no-auto-key-locate.

              nodefault
                     This flag disables the standard local  key  lookup,  done
                     before  any  of the mechanisms defined by the --auto-key-
                     locate are tried.  The position of this mechanism in  the
                     list  does  not  matter.   It is not required if local is
                     also used.

       --keyid-format short|0xshort|long|0xlong
              Select how to  display  key  IDs.  "short"  is  the  traditional
              8-character  key  ID.  "long"  is  the  more  accurate (but less
              convenient) 16-character key  ID.  Add  an  "0x"  to  either  to
              include  an  "0x"  at  the  beginning  of  the  key  ID,  as  in
              0x99242560.

       --keyserver name
              Use name as your keyserver. This is the server that --recv-keys,
              --send-keys,  and --search-keys will communicate with to receive
              keys from, send keys to, and search for keys on. The  format  of
              the  name is a URI: ‘scheme:[//]keyservername[:port]’ The scheme
              is the type of keyserver: "hkp" for  the  HTTP  (or  compatible)
              keyservers,  "ldap" for the LDAP keyservers, or "mailto" for the
              Graff email keyserver. Note that your particular installation of
              GnuPG   may  have  other  keyserver  types  available  as  well.
              Keyserver schemes  are  case-insensitive.  After  the  keyserver
              name,  optional keyserver configuration options may be provided.
              These are the same as the global --keyserver-options from below,
              but apply only to this particular keyserver.

              Most  keyservers  synchronize  with  each  other,  so  there  is
              generally no need to send keys to  more  than  one  server.  The
              keyserver  hkp://keys.gnupg.net  uses  round robin DNS to give a
              different keyserver each time you use it.

       --keyserver-options name=value1
              This is a space or comma delimited string that gives options for
              the  keyserver. Options can be prefixed with a ‘no-’ to give the
              opposite meaning. Valid import-options or export-options may  be
              used  here  as  well  to  apply  to  importing  (--recv-key)  or
              exporting (--send-key) a key from a  keyserver.  While  not  all
              options  are  available  for  all  keyserver  types, some common
              options are:

              include-revoked
                     When searching for a key with --search-keys, include keys
                     that  are  marked  on the keyserver as revoked. Note that
                     not all  keyservers  differentiate  between  revoked  and
                     unrevoked  keys,  and  for such keyservers this option is
                     meaningless. Note also that most keyservers do  not  have
                     cryptographic  verification  of  key  revocations, and so
                     turning this option off may result in skipping keys  that
                     are incorrectly marked as revoked.

              include-disabled
                     When searching for a key with --search-keys, include keys
                     that are marked on the keyserver as disabled.  Note  that
                     this option is not used with HKP keyservers.

              auto-key-retrieve
                     This option enables the automatic retrieving of keys from
                     a keyserver when verifying signatures made by  keys  that
                     are not on the local keyring.

                     Note  that  this  option  makes a "web bug" like behavior
                     possible.  Keyserver operators can  see  which  keys  you
                     request,  so  by  sending you a message signed by a brand
                     new key (which you naturally will not have on your  local
                     keyring),  the operator can tell both your IP address and
                     the time when you verified the signature.

              honor-keyserver-url
                     When using --refresh-keys, if the key in question  has  a
                     preferred   keyserver   URL,   then  use  that  preferred
                     keyserver to refresh the key from. In addition, if  auto-
                     key-retrieve is set, and the signature being verified has
                     a  preferred  keyserver  URL,  then  use  that  preferred
                     keyserver to fetch the key from. Defaults to yes.

              honor-pka-record
                     If  auto-key-retrieve  is  set,  and  the signature being
                     verified has a PKA record, then use the  PKA  information
                     to fetch the key. Defaults to yes.

              include-subkeys
                     When  receiving  a  key,  include  subkeys  as  potential
                     targets. Note that this  option  is  not  used  with  HKP
                     keyservers,  as  they  do  not support retrieving keys by
                     subkey id.

              use-temp-files
                     On most Unix-like platforms, GnuPG communicates with  the
                     keyserver  helper  program  via  pipes, which is the most
                     efficient  method.  This  option  forces  GnuPG  to   use
                     temporary  files  to communicate. On some platforms (such
                     as Win32 and RISC OS), this option is always enabled.

              keep-temp-files
                     If using ‘use-temp-files’, do not delete the  temp  files
                     after  using  them.  This  option  is useful to learn the
                     keyserver communication protocol by reading the temporary
                     files.

              verbose
                     Tell  the  keyserver  helper  program to be more verbose.
                     This option can be repeated multiple  times  to  increase
                     the verbosity level.

              timeout
                     Tell  the  keyserver helper program how long (in seconds)
                     to try and perform a keyserver action before  giving  up.
                     Note  that  performing  multiple actions at the same time
                     uses this timeout value per action.   For  example,  when
                     retrieving  multiple  keys  via  --recv-keys, the timeout
                     applies separately to each key retrieval, and not to  the
                     --recv-keys command as a whole. Defaults to 30 seconds.

              http-proxy=value
                     Set  the  proxy to use for HTTP and HKP keyservers.  This
                     overrides the "http_proxy" environment variable, if  any.

              max-cert-size
                     When  retrieving  a key via DNS CERT, only accept keys up
                     to this size.  Defaults to 16384 bytes.

              debug  Turn on debug output in  the  keyserver  helper  program.
                     Note  that  the  details of debug output depends on which
                     keyserver helper program is being used, and in  turn,  on
                     any  libraries  that  the  keyserver  helper program uses
                     internally (libcurl, openldap, etc).

              check-cert
                     Enable certificate checking if the keyserver presents one
                     (for hkps or ldaps).  Defaults to on.

              ca-cert-file
                     Provide   a  certificate  file  to  override  the  system
                     default.  Only necessary if check-cert  is  enabled,  and
                     the  keyserver is using a certificate that is not present
                     in a system default certificate list.

       --completes-needed n
              Number of completely trusted users to introduce a new key signer
              (defaults to 1).

       --marginals-needed n
              Number of marginally trusted users to introduce a new key signer
              (defaults to 3)

       --max-cert-depth n
              Maximum depth of a certification chain (default is 5).

       --simple-sk-checksum
              Secret keys are integrity protected by using a  SHA-1  checksum.
              This   method   is   part   of  the  upcoming  enhanced  OpenPGP
              specification but GnuPG already  uses  it  as  a  countermeasure
              against certain attacks.  Old applications don’t understand this
              new format, so this option may be used to switch back to the old
              behaviour.  Using  this  option bears a security risk. Note that
              using this option only takes  effect  when  the  secret  key  is
              encrypted  -  the  simplest way to make this happen is to change
              the passphrase on the key (even changing it to the same value is
              acceptable).

       --no-sig-cache
              Do not cache the verification status of key signatures.  Caching
              gives a much better performance in key listings. However, if you
              suspect  that  your  public  keyring  is  not save against write
              modifications, you can use this option to disable  the  caching.
              It  probably  does not make sense to disable it because all kind
              of damage can be done if someone else has write access  to  your
              public keyring.

       --no-sig-create-check
              GnuPG  normally  verifies each signature right after creation to
              protect against bugs and hardware malfunctions which could  leak
              out bits from the secret key. This extra verification needs some
              time (about 115% for DSA keys), and so this option can  be  used
              to  disable  it.   However,  due  to the fact that the signature
              creation needs manual interaction, this performance penalty does
              not matter in most settings.

       --auto-check-trustdb

       --no-auto-check-trustdb
              If  GnuPG  feels that its information about the Web of Trust has
              to be updated, it automatically runs the --check-trustdb command
              internally.   This  may  be a time consuming process. --no-auto-
              check-trustdb disables this option.

       --use-agent

       --no-use-agent
              Try to use the GnuPG-Agent.  With this option, GnuPG first tries
              to  connect  to the agent before it asks for a passphrase. --no-
              use-agent disables this option.

       --gpg-agent-info
              Override    the    value    of    the    environment    variable
              'GPG_AGENT_INFO'’.  This  is only used when --use-agent has been
              given.  Given that this option is not anymore used by  gpg2,  it
              should be avoided if possible.

       --lock-once
              Lock the databases the first time a lock is requested and do not
              release the lock until the process terminates.

       --lock-multiple
              Release the locks every time a lock is  no  longer  needed.  Use
              this to override a previous --lock-once from a config file.

       --lock-never
              Disable  locking  entirely.  This  option should be used only in
              very special environments, where it can be assured that only one
              process  is  accessing  those  files.  A  bootable floppy with a
              stand-alone encryption system will probably use  this.  Improper
              usage of this option may lead to data and key corruption.

       --exit-on-status-write-error
              This  option  will  cause  write  errors  on  the  status  FD to
              immediately terminate the process. That should in  fact  be  the
              default  but it never worked this way and thus we need an option
              to enable this, so that  the  change  won’t  break  applications
              which  close  their end of a status fd connected pipe too early.
              Using this option along  with  --enable-progress-filter  may  be
              used to cleanly cancel long running gpg operations.

       --limit-card-insert-tries n
              With  n  greater than 0 the number of prompts asking to insert a
              smartcard gets limited to N-1. Thus with a value of 1 gpg  won’t
              at  all  ask  to  insert  a  card  if  none has been inserted at
              startup. This option is useful in the configuration file in case
              an  application  does  not  know about the smartcard support and
              waits ad infinitum for an inserted card.

       --no-random-seed-file
              GnuPG uses a  file  to  store  its  internal  random  pool  over
              invocations.   This  makes  random  generation  faster;  however
              sometimes write operations are not desired. This option  can  be
              used  to achieve that with the cost of slower random generation.

       --no-greeting
              Suppress the initial copyright message.

       --no-secmem-warning
              Suppress the warning about "using insecure memory".

       --no-permission-warning
              Suppress the  warning  about  unsafe  file  and  home  directory
              (--homedir)  permissions.  Note  that the permission checks that
              GnuPG performs are not intended to be authoritative, but  rather
              they  simply  warn  about certain common permission problems. Do
              not assume that the lack of a warning means that your system  is
              secure.

              Note that the warning for unsafe --homedir permissions cannot be
              suppressed in the gpg.conf file, as this would allow an attacker
              to  place an unsafe gpg.conf file in place, and use this file to
              suppress  warnings  about  itself.  The  --homedir   permissions
              warning may only be suppressed on the command line.

       --no-mdc-warning
              Suppress the warning about missing MDC integrity protection.

       --require-secmem

       --no-require-secmem
              Refuse  to run if GnuPG cannot get secure memory. Defaults to no
              (i.e. run, but give a warning).

       --require-cross-certification

       --no-require-cross-certification
              When verifying a signature made from a subkey, ensure  that  the
              cross  certification  "back  signature" on the subkey is present
              and valid.   This  protects  against  a  subtle  attack  against
              subkeys   that   can   sign.    Defaults   to   --require-cross-
              certification for gpg.

       --expert

       --no-expert
              Allow the user to do certain nonsensical or "silly" things  like
              signing  an  expired  or  revoked  key,  or  certain potentially
              incompatible things like generating unusual key types. This also
              disables certain warning messages about potentially incompatible
              actions. As the name implies, this option is for  experts  only.
              If you don’t fully understand the implications of what it allows
              you to do, leave this off. --no-expert disables this option.

   Key related options

       --recipient name

       -r     Encrypt for user id name. If this option  or  --hidden-recipient
              is  not  specified, GnuPG asks for the user-id unless --default-
              recipient is given.

       --hidden-recipient name

       -R     Encrypt for user ID name, but hide the key  ID  of  this  user’s
              key.  This  option helps to hide the receiver of the message and
              is a limited countermeasure against traffic  analysis.  If  this
              option  or --recipient is not specified, GnuPG asks for the user
              ID unless --default-recipient is given.

       --encrypt-to name
              Same as --recipient but this one is  intended  for  use  in  the
              options  file  and  may  be  used  with  your  own user-id as an
              "encrypt-to-self". These keys are only used when there are other
              recipients  given  either  by use of --recipient or by the asked
              user id.  No trust checking is performed for these user ids  and
              even disabled keys can be used.

       --hidden-encrypt-to name
              Same  as  --hidden-recipient but this one is intended for use in
              the options file and may be used with  your  own  user-id  as  a
              hidden  "encrypt-to-self".  These  keys are only used when there
              are other recipients given either by use of  --recipient  or  by
              the  asked  user  id.   No trust checking is performed for these
              user ids and even disabled keys can be used.

       --no-encrypt-to
              Disable the use  of  all  --encrypt-to  and  --hidden-encrypt-to
              keys.

       --group name=value1
              Sets  up  a  named  group,  which is similar to aliases in email
              programs.  Any time  the  group  name  is  a  recipient  (-r  or
              --recipient),  it  will  be  expanded  to  the values specified.
              Multiple groups with the same name are automatically merged into
              a single group.

              The  values are key IDs or fingerprints, but any key description
              is accepted. Note that a value with spaces in it will be treated
              as  two  different  values. Note also there is only one level of
              expansion --- you cannot make an group that  points  to  another
              group.  When  used from the command line, it may be necessary to
              quote the argument to this option  to  prevent  the  shell  from
              treating it as multiple arguments.

       --ungroup name
              Remove a given entry from the --group list.

       --no-groups
              Remove all entries from the --group list.

       --local-user name

       -u     Use  name  as  the  key  to  sign  with.  Note  that this option
              overrides --default-key.

       --try-all-secrets
              Don’t look at the key ID as stored in the message  but  try  all
              secret  keys  in  turn  to  find  the right decryption key. This
              option forces the behaviour  as  used  by  anonymous  recipients
              (created  by  using --throw-keyids) and might come handy in case
              where an encrypted message contains a bogus key ID.

   Input and Output

       --armor

       -a     Create ASCII armored output.   The  default  is  to  create  the
              binary OpenPGP format.

       --no-armor
              Assume the input data is not in ASCII armored format.

       --output file

       -o file
              Write output to file.

       --max-output n
              This  option  sets  a  limit on the number of bytes that will be
              generated when processing a file. Since OpenPGP supports various
              levels  of  compression,  it is possible that the plaintext of a
              given message may be  significantly  larger  than  the  original
              OpenPGP  message. While GnuPG works properly with such messages,
              there is often a desire to set a maximum file size that will  be
              generated  before processing is forced to stop by the OS limits.
              Defaults to 0, which means "no limit".

       --import-options parameters
              This is a space or comma delimited string that gives options for
              importing  keys.  Options  can be prepended with a ‘no-’ to give
              the opposite meaning. The options are:

              import-local-sigs
                     Allow importing key signatures marked as "local". This is
                     not  generally  useful  unless a shared keyring scheme is
                     being used.  Defaults to no.

              repair-pks-subkey-bug
                     During import, attempt to repair the damage caused by the
                     PKS  keyserver  bug (pre version 0.9.6) that mangles keys
                     with multiple subkeys. Note that this  cannot  completely
                     repair the damaged key as some crucial data is removed by
                     the keyserver, but it does at least  give  you  back  one
                     subkey.  Defaults  to  no for regular --import and to yes
                     for keyserver --recv-keys.

              merge-only
                     During import, allow key updates to existing keys, but do
                     not allow any new keys to be imported. Defaults to no.

              import-clean
                     After  import,  compact (remove all signatures except the
                     self-signature) any user IDs from the new  key  that  are
                     not usable.  Then, remove any signatures from the new key
                     that are not usable.  This includes signatures that  were
                     issued  by keys that are not present on the keyring. This
                     option is the same  as  running  the  --edit-key  command
                     "clean" after import. Defaults to no.

              import-minimal
                     Import  the  smallest  key  possible.  This  removes  all
                     signatures except the most recent self-signature on  each
                     user  ID.  This option is the same as running the --edit-
                     key command "minimize" after import.  Defaults to no.

       --export-options parameters
              This is a space or comma delimited string that gives options for
              exporting  keys.  Options  can be prepended with a ‘no-’ to give
              the opposite meaning. The options are:

              export-local-sigs
                     Allow exporting key signatures marked as "local". This is
                     not  generally  useful  unless a shared keyring scheme is
                     being used.  Defaults to no.

              export-attributes
                     Include attribute user IDs (photo IDs)  while  exporting.
                     This  is  useful  to  export keys if they are going to be
                     used by an OpenPGP program that does not accept attribute
                     user IDs. Defaults to yes.

              export-sensitive-revkeys
                     Include designated revoker information that was marked as
                     "sensitive". Defaults to no.

              export-reset-subkey-passwd
                     When  using  the  --export-secret-subkeys  command,  this
                     option resets the passphrases for all exported subkeys to
                     empty. This is useful when the exported subkey is  to  be
                     used  on an unattended machine where a passphrase doesn’t
                     necessarily make sense. Defaults to no.

              export-clean
                     Compact (remove all signatures from) user IDs on the  key
                     being  exported  if the user IDs are not usable. Also, do
                     not export any  signatures  that  are  not  usable.  This
                     includes signatures that were issued by keys that are not
                     present on the  keyring.  This  option  is  the  same  as
                     running  the  --edit-key  command  "clean"  before export
                     except that the local copy of the key  is  not  modified.
                     Defaults to no.

              export-minimal
                     Export  the  smallest  key  possible.  This  removes  all
                     signatures except the most recent self-signature on  each
                     user  ID.  This option is the same as running the --edit-
                     key command "minimize"  before  export  except  that  the
                     local copy of the key is not modified. Defaults to no.

       --with-colons
              Print  key  listings  delimited  by colons. Note that the output
              will be encoded in UTF-8  regardless  of  any  --display-charset
              setting. This format is useful when GnuPG is called from scripts
              and other programs as it is easily machine parsed.  The  details
              of  this  format are documented in the file ‘doc/DETAILS’, which
              is included in the GnuPG source distribution.

       --fixed-list-mode
              Do not merge primary user ID and  primary  key  in  --with-colon
              listing   mode   and  print  all  timestamps  as  seconds  since
              1970-01-01.

       --with-fingerprint
              Same as the command --fingerprint but changes only the format of
              the output and may be used together with another command.

   OpenPGP protocol specific options.

       -t, --textmode

       --no-textmode
              Treat  input  files  as  text  and  store  them  in  the OpenPGP
              canonical text form with standard "CRLF" line endings. This also
              sets  the  necessary  flags  to  inform  the  recipient that the
              encrypted or signed data is text and may need its  line  endings
              converted back to whatever the local system uses. This option is
              useful  when  communicating  between  two  platforms  that  have
              different  line  ending  conventions  (UNIX-like  to Mac, Mac to
              Windows, etc). --no-textmode disables this option,  and  is  the
              default.

              If  -t  (but  not --textmode) is used together with armoring and
              signing, this  enables  clearsigned  messages.  This  kludge  is
              needed for command-line compatibility with command-line versions
              of PGP; normally you would use --sign or --clearsign  to  select
              the type of the signature.

       --force-v3-sigs

       --no-force-v3-sigs
              OpenPGP   states  that  an  implementation  should  generate  v4
              signatures but PGP  versions  5  through  7  only  recognize  v4
              signatures on key material. This option forces v3 signatures for
              signatures on data.  Note that this  option  implies  --ask-sig-
              expire,  --sig-policy-url,  --sig-notation, and --sig-keyserver-
              url, as these features cannot be used with v3 signatures.  --no-
              force-v3-sigs disables this option.

       --force-v4-certs

       --no-force-v4-certs
              Always  use  v4 key signatures even on v3 keys. This option also
              changes the default hash algorithm for v3 RSA keys from  MD5  to
              SHA-1.  --no-force-v4-certs disables this option.

       --force-mdc
              Force  the use of encryption with a modification detection code.
              This is always  used  with  the  newer  ciphers  (those  with  a
              blocksize greater than 64 bits), or if all of the recipient keys
              indicate MDC support in their feature flags.

       --disable-mdc
              Disable the use of the modification detection code. Note that by
              using this option, the encrypted message becomes vulnerable to a
              message modification attack.

       --personal-cipher-preferences string
              Set the list of personal cipher preferences to string.  Use  gpg
              --version to get a list of available algorithms, and use none to
              set no preference at  all.   This  allows  the  user  to  safely
              override  the algorithm chosen by the recipient key preferences,
              as GPG will only select an  algorithm  that  is  usable  by  all
              recipients.   The most highly ranked cipher in this list is also
              used for the --symmetric encryption command.

       --personal-digest-preferences string
              Set the list of personal digest preferences to string.  Use  gpg
              --version to get a list of available algorithms, and use none to
              set no preference at  all.   This  allows  the  user  to  safely
              override  the algorithm chosen by the recipient key preferences,
              as GPG will only select an  algorithm  that  is  usable  by  all
              recipients.   The  most  highly  ranked digest algorithm in this
              list  is  also  used  when  signing  without  encryption   (e.g.
              --clearsign or --sign). The default value is SHA-1.

       --personal-compress-preferences string
              Set the list of personal compression preferences to string.  Use
              gpg --version to get a list of  available  algorithms,  and  use
              none  to  set  no  preference  at  all.  This allows the user to
              safely override  the  algorithm  chosen  by  the  recipient  key
              preferences, as GPG will only select an algorithm that is usable
              by all recipients.  The most highly ranked compression algorithm
              in  this  list  is also used when there are no recipient keys to
              consider (e.g. --symmetric).

       --s2k-cipher-algo name
              Use name as the cipher algorithm used to  protect  secret  keys.
              The  default  cipher  is  CAST5.  This  cipher  is also used for
              conventional  encryption  if  --personal-cipher-preferences  and
              --cipher-algo is not given.

       --s2k-digest-algo name
              Use name as the digest algorithm used to mangle the passphrases.
              The default algorithm is SHA-1.

       --s2k-mode n
              Selects  how  passphrases  are  mangled.  If  n  is  0  a  plain
              passphrase  (which  is not recommended) will be used, a 1 adds a
              salt to the passphrase and a 3 (the default) iterates the  whole
              process  a  number of times (see --s2k-count).  Unless --rfc1991
              is used, this mode is also used for conventional encryption.

       --s2k-count n
              Specify how many times  the  passphrase  mangling  is  repeated.
              This  value  may  range between 1024 and 65011712 inclusive, and
              the  default  is  65536.   Note  that  not  all  values  in  the
              1024-65011712  range  are  legal  and  if  an  illegal  value is
              selected, GnuPG will round up to the nearest legal value.   This
              option is only meaningful if --s2k-mode is 3.

   Compliance options

       These  options  control  what  GnuPG is compliant to. Only one of these
       options may be active at a time. Note that the default setting of  this
       is  nearly  always the correct one. See the INTEROPERABILITY WITH OTHER
       OPENPGP PROGRAMS section below before using one of these options.

       --gnupg
              Use  standard  GnuPG  behavior.  This  is  essentially   OpenPGP
              behavior  (see  --openpgp), but with some additional workarounds
              for common compatibility problems in different versions of  PGP.
              This  is  the default option, so it is not generally needed, but
              it may be useful to override a different  compliance  option  in
              the gpg.conf file.

       --openpgp
              Reset  all  packet,  cipher and digest options to strict OpenPGP
              behavior. Use this option to reset  all  previous  options  like
              --s2k-*,  --cipher-algo,  --digest-algo  and  --compress-algo to
              OpenPGP compliant values. All PGP workarounds are disabled.

       --rfc4880
              Reset all packet, cipher and digest options to  strict  RFC-4880
              behavior.  Note  that  this  is  currently  the  same  thing  as
              --openpgp.

       --rfc2440
              Reset all packet, cipher and digest options to  strict  RFC-2440
              behavior.

       --rfc1991
              Try to be more RFC-1991 (PGP 2.x) compliant.

       --pgp2 Set  up  all options to be as PGP 2.x compliant as possible, and
              warn if an action is taken (e.g. encrypting to  a  non-RSA  key)
              that  will  create  a  message  that PGP 2.x will not be able to
              handle. Note that ‘PGP 2.x’ here means ‘MIT  PGP  2.6.2’.  There
              are  other versions of PGP 2.x available, but the MIT release is
              a good common baseline.

              This option implies --rfc1991 --disable-mdc  --no-force-v4-certs
              --escape-from-lines --force-v3-sigs --cipher-algo IDEA --digest-
              algo MD5 --compress-algo ZIP. It also disables  --textmode  when
              encrypting.

       --pgp6 Set  up  all  options to be as PGP 6 compliant as possible. This
              restricts you to  the  ciphers  IDEA  (if  the  IDEA  plugin  is
              installed), 3DES, and CAST5, the hashes MD5, SHA1 and RIPEMD160,
              and the compression algorithms none and ZIP. This also  disables
              --throw-keyids,  and  making  signatures with signing subkeys as
              PGP 6 does not understand signatures made by signing subkeys.

              This option implies --disable-mdc  --escape-from-lines  --force-
              v3-sigs.

       --pgp7 Set up all options to be as PGP 7 compliant as possible. This is
              identical to --pgp6 except that MDCs are not disabled,  and  the
              list  of  allowable  ciphers  is expanded to add AES128, AES192,
              AES256, and TWOFISH.

       --pgp8 Set up all options to be as PGP 8 compliant as possible.  PGP  8
              is  a  lot closer to the OpenPGP standard than previous versions
              of PGP, so all this  does  is  disable  --throw-keyids  and  set
              --escape-from-lines.   All algorithms are allowed except for the
              SHA224, SHA384, and SHA512 digests.

   Doing things one usually doesnt want to do.

       -n

       --dry-run
              Don’t make any changes (this is not completely implemented).

       --list-only
              Changes the behaviour of some commands. This is  like  --dry-run
              but different in some cases. The semantic of this command may be
              extended in the future.  Currently  it  only  skips  the  actual
              decryption  pass  and  therefore  enables  a fast listing of the
              encryption keys.

       -i

       --interactive
              Prompt before overwriting any files.

       --debug flags
              Set debugging flags. All flags are or-ed and flags may be  given
              in C syntax (e.g. 0x0042).

       --debug-all
              Set all useful debugging flags.

       --debug-ccid-driver
              Enable   debug   output   from  the  included  CCID  driver  for
              smartcards.  Note that this option is  only  available  on  some
              system.

       --enable-progress-filter
              Enable  certain  PROGRESS  status  outputs.  This  option allows
              frontends  to  display  a  progress  indicator  while   gpg   is
              processing larger files.  There is a slight performance overhead
              using it.

       --status-fd n
              Write special status strings to the file descriptor n.  See  the
              file DETAILS in the documentation for a listing of them.

       --status-file file
              Same  as  --status-fd, except the status data is written to file
              file.

       --logger-fd n
              Write log output to file descriptor n and not to STDERR.

       --log-file file

       --logger-file file
              Same as --logger-fd, except the logger data is written  to  file
              file.  Note that --log-file is only implemented for GnuPG-2.

       --attribute-fd n
              Write  attribute  subpackets  to  the file descriptor n. This is
              most useful for use with --status-fd, since the status  messages
              are  needed  to  separate  out  the  various subpackets from the
              stream delivered to the file descriptor.

       --attribute-file file
              Same as --attribute-fd, except the attribute data is written  to
              file file.

       --comment string

       --no-comments
              Use  string  as  a  comment  string in clear text signatures and
              ASCII armored  messages  or  keys  (see  --armor).  The  default
              behavior  is  not  to  use  a  comment  string. --comment may be
              repeated multiple times to get multiple comment  strings.  --no-
              comments  removes  all  comments.  It is a good idea to keep the
              length of a single comment below 60 characters to avoid problems
              with  mail  programs  wrapping  such  lines.   Note that comment
              lines, like all other header lines, are  not  protected  by  the
              signature.

       --emit-version

       --no-emit-version
              Force  inclusion  of the version string in ASCII armored output.
              --no-emit-version disables this option.

       --sig-notation name=value

       --cert-notation name=value

       -N, --set-notation name=value
              Put the name value pair into the  signature  as  notation  data.
              name  must  consist  only of printable characters or spaces, and
              must    contain    a    ’@’    character     in     the     form
              keyname@domain.example.com (substituting the appropriate keyname
              and domain name, of course).  This is to help prevent  pollution
              of  the  IETF  reserved  notation  namespace.  The --expert flag
              overrides the ’@’ check. value may be any printable  string;  it
              will  be  encoded  in  UTF8,  so  you  should  check  that  your
              --display-charset is set correctly. If you prefix name  with  an
              exclamation  mark  (!),  the  notation  data  will be flagged as
              critical (rfc2440:5.2.3.15). --sig-notation sets a notation  for
              data   signatures.  --cert-notation  sets  a  notation  for  key
              signatures (certifications). --set-notation sets both.

              There are special codes that may be used in notation names. "%k"
              will  be  expanded into the key ID of the key being signed, "%K"
              into the long key ID of the key  being  signed,  "%f"  into  the
              fingerprint of the key being signed, "%s" into the key ID of the
              key making the signature, "%S" into the long key ID of  the  key
              making  the  signature,  "%g"  into  the  fingerprint of the key
              making the signature (which might be a subkey),  "%p"  into  the
              fingerprint  of the primary key of the key making the signature,
              "%c" into the signature count from the  OpenPGP  smartcard,  and
              "%%" results in a single "%". %k, %K, and %f are only meaningful
              when making a key signature  (certification),  and  %c  is  only
              meaningful when using the OpenPGP smartcard.

       --sig-policy-url string

       --cert-policy-url string

       --set-policy-url string
              Use  string  as  a Policy URL for signatures (rfc2440:5.2.3.19).
              If you prefix it with an exclamation mark (!),  the  policy  URL
              packet  will  be  flagged  as  critical. --sig-policy-url sets a
              policy url for data signatures. --cert-policy-url sets a  policy
              url  for  key signatures (certifications). --set-policy-url sets
              both.

              The same %-expandos used for notation data are available here as
              well.

       --sig-keyserver-url string
              Use  string as a preferred keyserver URL for data signatures. If
              you prefix it with an exclamation mark (!),  the  keyserver  URL
              packet will be flagged as critical.

              The same %-expandos used for notation data are available here as
              well.

       --set-filename string
              Use string as the filename  which  is  stored  inside  messages.
              This  overrides the default, which is to use the actual filename
              of the file being encrypted.

       --for-your-eyes-only

       --no-for-your-eyes-only
              Set the ‘for your eyes only’ flag in the  message.  This  causes
              GnuPG  to  refuse to save the file unless the --output option is
              given, and PGP to use a "secure viewer" with a claimed  Tempest-
              resistant  font  to  display  the message. This option overrides
              --set-filename.  --no-for-your-eyes-only disables this option.

       --use-embedded-filename

       --no-use-embedded-filename
              Try to create a file with a name as embedded in the  data.  This
              can  be  a  dangerous  option  as  it allows to overwrite files.
              Defaults to no.

       --cipher-algo name
              Use name as cipher  algorithm.  Running  the  program  with  the
              command --version yields a list of supported algorithms. If this
              is  not  used  the  cipher  algorithm  is  selected   from   the
              preferences  stored with the key. In general, you do not want to
              use this  option  as  it  allows  you  to  violate  the  OpenPGP
              standard.   --personal-cipher-preferences  is  the  safe  way to
              accomplish the same thing.

       --digest-algo name
              Use name as the message digest algorithm.  Running  the  program
              with   the   command   --version  yields  a  list  of  supported
              algorithms. In general, you do not want to use this option as it
              allows  you  to violate the OpenPGP standard. --personal-digest-
              preferences is the safe way to accomplish the same thing.

       --compress-algo name
              Use  compression  algorithm  name.  "zlib"  is   RFC-1950   ZLIB
              compression.  "zip" is RFC-1951 ZIP compression which is used by
              PGP.  "bzip2" is a  more  modern  compression  scheme  that  can
              compress some things better than zip or zlib, but at the cost of
              more  memory  used   during   compression   and   decompression.
              "uncompressed" or "none" disables compression. If this option is
              not used, the default behavior is to examine the  recipient  key
              preferences  to  see which algorithms the recipient supports. If
              all else fails, ZIP is used for maximum compatibility.

              ZLIB may give  better  compression  results  than  ZIP,  as  the
              compression  window  size  is  not limited to 8k. BZIP2 may give
              even better compression  results  than  that,  but  will  use  a
              significantly  larger  amount  of  memory  while compressing and
              decompressing. This may be significant in low memory situations.
              Note,  however,  that  PGP  (all  versions)  only  supports  ZIP
              compression. Using any algorithm other than ZIP or  "none"  will
              make  the  message  unreadable  with PGP. In general, you do not
              want to use this option as it allows you to violate the  OpenPGP
              standard.  --personal-compress-preferences  is  the  safe way to
              accomplish the same thing.

       --cert-digest-algo name
              Use name as the message digest algorithm  used  when  signing  a
              key.  Running  the  program  with the command --version yields a
              list of supported algorithms. Be aware that  if  you  choose  an
              algorithm  that GnuPG supports but other OpenPGP implementations
              do not, then some  users  will  not  be  able  to  use  the  key
              signatures you make, or quite possibly your entire key.

       --disable-cipher-algo name
              Never allow the use of name as cipher algorithm.  The given name
              will not be checked so that a later loaded algorithm will  still
              get disabled.

       --disable-pubkey-algo name
              Never  allow the use of name as public key algorithm.  The given
              name will not be checked so that a later loaded  algorithm  will
              still get disabled.

       --throw-keyids

       --no-throw-keyids
              Do  not  put the recipient key IDs into encrypted messages. This
              helps to hide the receivers of the  message  and  is  a  limited
              countermeasure against traffic analysis. ([Using a little social
              engineering anyone who is able to decrypt the message can  check
              whether  one  of  the other recipients is the one he suspects.])
              On the receiving side, it may slow down the  decryption  process
              because  all  available  secret keys must be tried.  --no-throw-
              keyids disables this option. This option is essentially the same
              as using --hidden-recipient for all recipients.

       --not-dash-escaped
              This option changes the behavior of cleartext signatures so that
              they can be used for patch files. You should not  send  such  an
              armored  file  via email because all spaces and line endings are
              hashed too. You can not use this option for  data  which  has  5
              dashes  at the beginning of a line, patch files don’t have this.
              A special armor header line tells  GnuPG  about  this  cleartext
              signature option.

       --escape-from-lines

       --no-escape-from-lines
              Because  some  mailers  change  lines  starting  with "From " to
              ">From " it is good to handle such lines in a special  way  when
              creating  cleartext  signatures  to prevent the mail system from
              breaking the signature. Note that all other PGP versions  do  it
              this   way  too.   Enabled  by  default.  --no-escape-from-lines
              disables this option.

       --passphrase-repeat n
              Specify how many times gpg will  request  a  new  passphrase  be
              repeated.   This  is  useful  for helping memorize a passphrase.
              Defaults to 1 repetition.

       --passphrase-fd n
              Read the passphrase from file descriptor n. Only the first  line
              will  be  read  from  file descriptor n. If you use 0 for n, the
              passphrase will be read from STDIN. This can  only  be  used  if
              only one passphrase is supplied.

       --passphrase-file file
              Read  the passphrase from file file. Only the first line will be
              read from  file  file.  This  can  only  be  used  if  only  one
              passphrase is supplied. Obviously, a passphrase stored in a file
              is of questionable security if other users can read  this  file.
              Don’t use this option if you can avoid it.

       --passphrase string
              Use  string as the passphrase. This can only be used if only one
              passphrase is supplied. Obviously, this is of very  questionable
              security  on  a  multi-user system. Don’t use this option if you
              can avoid it.

       --command-fd n
              This is a replacement for the deprecated shared-memory IPC mode.
              If  this  option  is  enabled,  user  input  on questions is not
              expected from the TTY but from the  given  file  descriptor.  It
              should   be   used  together  with  --status-fd.  See  the  file
              doc/DETAILS in the source distribution for details on how to use
              it.

       --command-file file
              Same  as  --command-fd, except the commands are read out of file
              file

       --allow-non-selfsigned-uid

       --no-allow-non-selfsigned-uid
              Allow the import and use of keys with user  IDs  which  are  not
              self-signed.  This is not recommended, as a non self-signed user
              ID is trivial to forge. --no-allow-non-selfsigned-uid  disables.

       --allow-freeform-uid
              Disable all checks on the form of the user ID while generating a
              new one. This  option  should  only  be  used  in  very  special
              environments  as it does not ensure the de-facto standard format
              of user IDs.

       --ignore-time-conflict
              GnuPG normally checks that the timestamps associated  with  keys
              and  signatures  have  plausible  values.  However,  sometimes a
              signature seems to be older than the key due to clock  problems.
              This  option  makes  these  checks  just  a  warning.  See  also
              --ignore-valid-from for timestamp issues on subkeys.

       --ignore-valid-from
              GnuPG normally does not select and use subkeys  created  in  the
              future.   This  option  allows  the  use  of  such keys and thus
              exhibits the pre-1.0.7 behaviour. You should not use this option
              unless  you there is some clock problem. See also --ignore-time-
              conflict for timestamp issues with signatures.

       --ignore-crc-error
              The ASCII armor used by OpenPGP is protected by a  CRC  checksum
              against  transmission  errors. Occasionally the CRC gets mangled
              somewhere on the transmission channel  but  the  actual  content
              (which  is  protected  by  the OpenPGP protocol anyway) is still
              okay. This option allows GnuPG to ignore CRC errors.

       --ignore-mdc-error
              This option changes a MDC integrity protection  failure  into  a
              warning.   This can be useful if a message is partially corrupt,
              but it is necessary to get as much data as possible out  of  the
              corrupt  message.   However,  be  aware  that  a  MDC protection
              failure may  also  mean  that  the  message  was  tampered  with
              intentionally by an attacker.

       --no-default-keyring
              Do  not  add  the default keyrings to the list of keyrings. Note
              that GnuPG will not operate without any keyrings, so if you  use
              this  option and do not provide alternate keyrings via --keyring
              or --secret-keyring, then  GnuPG  will  still  use  the  default
              public or secret keyrings.

       --skip-verify
              Skip  the  signature verification step. This may be used to make
              the decryption faster  if  the  signature  verification  is  not
              needed.

       --with-key-data
              Print  key listings delimited by colons (like --with-colons) and
              print the public key data.

       --fast-list-mode
              Changes the output of the list commands to work faster; this  is
              achieved  by  leaving  some parts empty. Some applications don’t
              need the  user  ID  and  the  trust  information  given  in  the
              listings.  By  using this options they can get a faster listing.
              The  exact  behaviour  of  this  option  may  change  in  future
              versions.   If  you are missing some information, don’t use this
              option.

       --no-literal
              This is not for normal use. Use the source to see  for  what  it
              might be useful.

       --set-filesize
              This  is  not  for normal use. Use the source to see for what it
              might be useful.

       --show-session-key
              Display the session key used for one  message.  See  --override-
              session-key for the counterpart of this option.

              We think that Key Escrow is a Bad Thing; however the user should
              have the freedom to decide whether to go to prison or to  reveal
              the  content  of  one  specific message without compromising all
              messages ever encrypted for one secret key. DON’T USE IT  UNLESS
              YOU ARE REALLY FORCED TO DO SO.

       --override-session-key string
              Don’t  use the public key but the session key string. The format
              of this string is the same as the one printed by --show-session-
              key.  This  option  is normally not used but comes handy in case
              someone forces  you  to  reveal  the  content  of  an  encrypted
              message;  using  this option you can do this without handing out
              the secret key.

       --ask-sig-expire

       --no-ask-sig-expire
              When making a data signature, prompt for an expiration time.  If
              this  option  is  not  specified,  the  expiration  time set via
              --default-sig-expire is used. --no-ask-sig-expire disables  this
              option.  Note that by default, --force-v3-sigs is set which also
              disables this option. If you want signature expiration, you must
              set --no-force-v3-sigs as well as turning --ask-sig-expire on.

       --default-sig-expire
              The  default  expiration  time  to use for signature expiration.
              Valid values are "0" for no expiration, a number followed by the
              letter  d  (for  days), w (for weeks), m (for months), or y (for
              years) (for example "2m"  for  two  months,  or  "5y"  for  five
              years),  or an absolute date in the form YYYY-MM-DD. Defaults to
              "0".

       --ask-cert-expire

       --no-ask-cert-expire
              When making a key signature, prompt for an expiration  time.  If
              this  option  is  not  specified,  the  expiration  time set via
              --default-cert-expire  is  used.  --no-ask-cert-expire  disables
              this option.

       --default-cert-expire
              The default expiration time to use for key signature expiration.
              Valid values are "0" for no expiration, a number followed by the
              letter  d  (for  days), w (for weeks), m (for months), or y (for
              years) (for example "2m"  for  two  months,  or  "5y"  for  five
              years),  or an absolute date in the form YYYY-MM-DD. Defaults to
              "0".

       --allow-secret-key-import
              This is an obsolete option and is not used anywhere.

       --allow-multiple-messages

       --no-allow-multiple-messages
              Allow processing of multiple OpenPGP  messages  contained  in  a
              single  file  or  stream.   Some  programs that call GPG are not
              prepared  to  deal  with  multiple  messages   being   processed
              together,  so this option defaults to no.  Note that versions of
              GPG prior to 1.4.7 always allowed multiple messages.

              Warning: Do not  use  this  option  unless  you  need  it  as  a
              temporary workaround!

       --enable-special-filenames
              This  options  enables  a  mode  in  which filenames of the form
              ‘-&n’, where n is a non-negative decimal number,  refer  to  the
              file descriptor n and not to a file with that name.

       --no-expensive-trust-checks
              Experimental use only.

       --preserve-permissions
              Don’t  change  the  permissions of a secret keyring back to user
              read/write only. Use this option only if you  really  know  what
              you are doing.

       --default-preference-list string
              Set  the  list of default preferences to string. This preference
              list is used for new keys and becomes the default for  "setpref"
              in the edit menu.

       --default-keyserver-url name
              Set  the  default  keyserver URL to name. This keyserver will be
              used as the keyserver URL when writing a new self-signature on a
              key, which includes key generation and changing preferences.

       --list-config
              Display various internal configuration parameters of GnuPG. This
              option is intended for external  programs  that  call  GnuPG  to
              perform  tasks,  and  is thus not generally useful. See the file
              ‘doc/DETAILS’ in the source  distribution  for  the  details  of
              which  configuration  items may be listed. --list-config is only
              usable with --with-colons set.

       --gpgconf-list
              This command is similar to --list-config  but  in  general  only
              internally used by the gpgconf tool.

       --gpgconf-test
              This  is  more  or  less  dummy  action.   However it parses the
              configuration file and returns with failure if the configuration
              file would prevent gpg from startup.  Thus it may be used to run
              a syntax check on the configuration file.

   Deprecated options

       --load-extension name
              Load an extension module. If name does not contain a slash it is
              searched  for  in  the directory configured when GnuPG was built
              (generally "/usr/local/lib/gnupg"). Extensions are not generally
              useful anymore, and the use of this option is deprecated.

       --show-photos

       --no-show-photos
              Causes  --list-keys,  --list-sigs,  --list-public-keys,  --list-
              secret-keys, and verifying a signature to also display the photo
              ID  attached  to the key, if any. See also --photo-viewer. These
              options  are  deprecated.  Use  --list-options  [no-]show-photos
              and/or --verify-options [no-]show-photos instead.

       --show-keyring
              Display  the  keyring  name  at the head of key listings to show
              which keyring a given key resides on. This option is deprecated:
              use --list-options [no-]show-keyring instead.

       --ctapi-driver file
              Use  file to access the smartcard reader. The current default is
              ‘libtowitoko.so’.  Note  that  the  use  of  this  interface  is
              deprecated; it may be removed in future releases.

       --always-trust
              Identical to --trust-model always. This option is deprecated.

       --show-notation

       --no-show-notation
              Show  signature  notations  in  the  --list-sigs or --check-sigs
              listings as well as when verifying a signature with  a  notation
              in   it.   These  options  are  deprecated.  Use  --list-options
              [no-]show-notation  and/or  --verify-options  [no-]show-notation
              instead.

       --show-policy-url

       --no-show-policy-url
              Show  policy URLs in the --list-sigs or --check-sigs listings as
              well as when verifying a signature with  a  policy  URL  in  it.
              These  options  are  deprecated.  Use  --list-options [no-]show-
              policy-url and/or --verify-options [no-]show-policy-url instead.

EXAMPLES

       gpg -se -r Bob file
              sign and encrypt for user Bob

       gpg --clearsign file
              make a clear text signature

       gpg -sb file
              make a detached signature

       gpg -u 0x12345678 -sb file
              make a detached signature with the key 0x12345678

       gpg --list-keys user_ID
              show keys

       gpg --fingerprint user_ID
              show fingerprint

       gpg --verify pgpfile

       gpg --verify sigfile
              Verify the signature of the file but do not output the data. The
              second form is used for detached signatures,  where  sigfile  is
              the  detached signature (either ASCII armored or binary) and are
              the signed data; if this is not given,  the  name  of  the  file
              holding  the  signed  data  is  constructed  by  cutting off the
              extension (".asc" or ".sig") of sigfile or by  asking  the  user
              for the filename.

HOW TO SPECIFY A USER ID

       There  are  different ways to specify a user ID to GnuPG.  Some of them
       are only valid for gpg others are only good for  gpgsm.   Here  is  the
       entire list of ways to specify a key:

       By key Id.
              This  format  is  deduced  from the length of the string and its
              content or 0x prefix. The key Id of an X.509 certificate are the
              low  64  bits  of  its SHA-1 fingerprint.  The use of key Ids is
              just a shortcut, for all automated  processing  the  fingerprint
              should be used.

              When  using gpg an exclamation mark (!) may be appended to force
              using the specified primary or secondary key and not to try  and
              calculate which primary or secondary key to use.

              The last four lines of the example give the key ID in their long
              form as internally used by the OpenPGP protocol. You can see the
              long key ID using the option --with-colons.

         234567C4
         0F34E556E
         01347A56A
         0xAB123456

         234AABBCC34567C4
         0F323456784E56EAB
         01AB3FED1347A5612
         0x234AABBCC34567C4

       By fingerprint.
              This  format  is  deduced  from the length of the string and its
              content or the 0x prefix.  Note, that only the 20  byte  version
              fingerprint  is available with gpgsm (i.e. the SHA-1 hash of the
              certificate).

              When using gpg an exclamation mark (!) may be appended to  force
              using  the specified primary or secondary key and not to try and
              calculate which primary or secondary key to use.

              The best way to specify a key Id is by  using  the  fingerprint.
              This  avoids  any  ambiguities in case that there are duplicated
              key IDs.

         1234343434343434C434343434343434
         123434343434343C3434343434343734349A3434
         0E12343434343434343434EAB3484343434343434
         0xE12343434343434343434EAB3484343434343434

       (gpgsm also accepts colons between  each  pair  of  hexadecimal  digits
       because  this  is  the  de-facto  standard  on  how  to  present  X.509
       fingerprints.)

       By exact match on OpenPGP user ID.
              This is denoted by a leading equal sign. It does not make  sense
              for X.509 certificates.

         =Heinrich Heine <heinrichh@uni-duesseldorf.de>

       By exact match on an email address.
              This  is  indicated  by enclosing the email address in the usual
              way with left and right angles.

         <heinrichh@uni-duesseldorf.de>

       By word match.
              All words must match exactly (not case sensitive) but can appear
              in  any  order in the user ID or a subjects name.  Words are any
              sequences of letters, digits, the underscore and all  characters
              with bit 7 set.

         +Heinrich Heine duesseldorf

       By exact match on the subjects DN.
              This  is  indicated by a leading slash, directly followed by the
              RFC-2253 encoded DN of the subject.  Note that you can’t use the
              string  printed  by "gpgsm --list-keys" because that one as been
              reordered and modified for better readability; use --with-colons
              to print the raw (but standard escaped) RFC-2253 string

         /CN=Heinrich Heine,O=Poets,L=Paris,C=FR

       By exact match on the issuers DN.
              This is indicated by a leading hash mark, directly followed by a
              slash and then directly followed by the rfc2253  encoded  DN  of
              the  issuer.   This  should  return the Root cert of the issuer.
              See note above.

         #/CN=Root Cert,O=Poets,L=Paris,C=FR

       By exact match on serial number and issuers DN.
              This is indicated by a hash mark, followed  by  the  hexadecimal
              representation  of  the  serial number, then followed by a slash
              and the RFC-2253 encoded DN of the issuer. See note above.

         #4F03/CN=Root Cert,O=Poets,L=Paris,C=FR

       By keygrip
              This is indicated by an ampersand followed by the 40 hex  digits
              of  a  keygrip.  gpgsm prints the keygrip when using the command
              --dump-cert.  It does not yet work for OpenPGP keys.

         &D75F22C3F86E355877348498CDC92BD21010A480

       By substring match.
              This is the default mode but applications may want to explicitly
              indicate  this  by  putting the asterisk in front.  Match is not
              case sensitive.

         Heine
         *Heine

       Please note that we have reused the hash mark identifier which was used
       in  old  GnuPG  versions to indicate the so called local-id.  It is not
       anymore used and there should be  no  conflict  when  used  with  X.509
       stuff.

       Using  the  RFC-2253  format  of  DNs  has  the drawback that it is not
       possible to map them back to the original encoding,  however  we  don’t
       have  to  do this because our key database stores this encoding as meta
       data.

FILES

       There are a few configuration files to control certain aspects of gpg’s
       operation.  Unless  noted,  they  are  expected  in  the  current  home
       directory (see: [option --homedir]).

       gpg.conf
              This is the standard configuration file read by gpg on  startup.
              It may contain any valid long option; the leading two dashes may
              not be entered and the option  may  not  be  abbreviated.   This
              default  name  may  be changed on the command line (see: [option
              --options]).  You should backup this file.

       Note that on larger installations, it is useful to put predefined files
       into  the  directory  ‘/etc/skel/.gnupg/’  so  that newly created users
       start up with a working configuration.

       For internal purposes gpg creates and maintains a few other files; They
       all  live  in  in the current home directory (see: [option --homedir]).
       Only the gpg may modify these files.

       ~/.gnupg/secring.gpg
              The secret keyring.  You should backup this file.

       ~/.gnupg/secring.gpg.lock
              The lock file for the secret keyring.

       ~/.gnupg/pubring.gpg
              The public keyring.  You should backup this file.

       ~/.gnupg/pubring.gpg.lock
              The lock file for the public keyring.

       ~/.gnupg/trustdb.gpg
              The trust database.  There is no need to backup this file; it is
              better  to  backup the ownertrust values (see: [option --export-
              ownertrust]).

       ~/.gnupg/trustdb.gpg.lock
              The lock file for the trust database.

       ~/.gnupg/random_seed
              A file used to preserve the state of the internal random pool.

       /usr[/local]/share/gnupg/options.skel
              The skeleton options file.

       /usr[/local]/lib/gnupg/
              Default location for extensions.

       Operation is further controlled by a few environment variables:

       HOME   Used to locate the default home directory.

       GNUPGHOME
              If set directory used instead of "~/.gnupg".

       GPG_AGENT_INFO
              Used to locate the gpg-agent.  This is only honored when  --use-
              agent  is  set.  The value consists of 3 colon delimited fields:
              The first is the path to the Unix Domain Socket, the second  the
              PID  of  the  gpg-agent and the protocol version which should be
              set to 1. When  starting  the  gpg-agent  as  described  in  its
              documentation,  this  variable  is set to the correct value. The
              option --gpg-agent-info can be used to override it.

       PINENTRY_USER_DATA
              This value is passed via gpg-agent to pinentry.  It is useful to
              convey extra information to a custom pinentry.

       COLUMNS

       LINES  Used to size some displays to the full size of the screen.

       LANGUAGE
              Apart  from  its  use  by  GNU, it is used in the W32 version to
              override the language selection done through the  Registry.   If
              used  and  set  to a valid and available language name (langid),
              the   file    with    the    translation    is    loaded    from
              gpgdir/gnupg.nls/langid.mo.  Here gpgdir is the directory out of
              which the gpg binary has been loaded.  If it can’t be loaded the
              Registry  is  tried and as last resort the native Windows locale
              system is used.

BUGS

       On many systems this program should be installed as setuid(root).  This
       is  necessary  to  lock memory pages. Locking memory pages prevents the
       operating  system  from  writing  memory  pages  (which   may   contain
       passphrases or other sensitive material) to disk. If you get no warning
       message about insecure memory your operating  system  supports  locking
       without being root. The program drops root privileges as soon as locked
       memory is allocated.

       Note also that some systems (especially laptops) have  the  ability  to
       ‘‘suspend  to  disk’’  (also known as ‘‘safe sleep’’ or ‘‘hibernate’’).
       This writes all memory to disk before going into a low  power  or  even
       powered off mode.  Unless measures are taken in the operating system to
       protect the saved memory, passphrases or other sensitive  material  may
       be recoverable from it later.

SEE ALSO

       gpgv(1),

       The full documentation for this tool is maintained as a Texinfo manual.
       If GnuPG and the info program are properly installed at your site,  the
       command

         info gnupg

       should  give  you  access  to  the  complete  manual  including  a menu
       structure and an index.