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NAME

       parse_opts - parse standard and user options for LTP test programs

SYNOPSIS

       #includetest.h#includeusctest.hchar *parse_opts(int argc, char *argv[],
                        option_t option_array[],
                        void (*user_help_func)());

DESCRIPTION

       The  parse_opts() routine parses options from the command line, looking
       for user  specified  options  or  standard  options  (see  below).  Its
       arguments  argc  and argv are the argument count and array as passed to
       the  main()  function  on  program  invocation.  User  options  may  be
       specified  in  the  option_array  argument.  A  help  function  may  be
       specified in the user_help_func argument.

       option_array is a pointer to the first element of an array of option_t.
       If  no  additional options are needed, pass NULL.  option_t is declared
       in usctest.h as

          typedef struct {
              char *option;
              int  *flag;
              char **arg;
          } option_t;

       The meanings of the different fields are:

       option is a valid option string to be given to getopt().

       flag   is a pointer to an integer location to set  true  if  option  is
              given  in  argv.  This can be NULL if the option doesn’t require
              an argument.

       arg    is a pointer to a character pointer variable that  will  be  set
              with the option argument if the option is present in argv.  This
              pointer MUST be provided if the option  can  take  an  argument.
              Failure  to provide a location will cause parse_opts() to return
              an error.

       user_help_func is a pointer to a function that will be called when  the
       -h  option  is found.  This function should print help messages for the
       options in option_array to standard out. The standard help messages are
       formatted  such  that  the option designator starts in column 3 and the
       description starts in column 11.

STANDARD OPTIONS

       Below is a list of the standard options defined in parse_opts():

       -c n   Run n copies of the test in parallel.  This is done by forking n
              times and running the test as usual.  If -i or -I are specified,
              each process will run for that amount of time.

       -e     Turn on  logging  all  errno’s  received.   This  option  is  to
              facilitate security audit testing for MLS.

       -f     Suppresses functional testing messages.

       -h     Print help message.  The standard options will be printed first,
              then a call to user_help_func() will be made.

       -i n   Run for  n  iterations.  A  value  of  0  makes  the  test  loop
              infinitely.  (default 1)

       -I x   The test will loop until x seconds have passed. (default 0.0)

       -p     Pause  for  SIGUSR1 before testing. The test will pause were you
              place TEST_PAUSE.  Warning: The test  will  also  fork  at  this
              point if -c is used.

       -P x   This  option  will do a delay of x seconds after each iteration.
              (default 0.0)

       -t     Produce timing statistics. *NOT IMPLEMENTED*

       The STD_* flags  are  used  by  system  call  test  macros  defined  in
       usctest.h (see usctest(3)), or may be used in the user’s code.

RETURN VALUE

       parse_opts()  returns a NULL pointer upon successful completion.  If an
       error occurs a pointer to an error message is returned.

EXAMPLE

       The following example defines two options, one with  an  argument,  one
       without.

       int fflag, Tflag;   /* binary flags: opt or not */
       char *Topt;         /* option arguments */

       option_t options[] = {
            { "F", &fflag, NULL },        /* No argument */
            { "T:",   &Tflag, &Topt },    /* argument required */
            { NULL, NULL, NULL }          /* NULL required to end array */
       };

       void help()
       {
            printf("  -F       An option with no argument\n");
            printf("  -T opt   An option that requires an argument\n");
       }

       int main(int argc, char *argv[])
       {
            char *msg;

            if ( (msg=parse_opts(argc, argv, options, &help)) != NULL )
                 error_exit(msg);

            return 0;
       }

       The  following  example  shows how to use parse_opts() without defining
       new options.

       int main(int argc, char *argv[])
       {
            char *msg;

            if ((msg=parse_opts(argc, argv, (option_t *)NULL, NULL)) != NULL)
                 error_exit(msg);

            return 0;
       }

SEE ALSO

       usctest(3), getopt(3).