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NAME

       explain_bind - explain bind(2) errors

SYNOPSIS

       #include <libexplain/bind.h>
       const  char *explain_bind(int fildes, const struct sockaddr *sock_addr,
       int sock_addr_size);
       const char *explain_errno_bind(int errnum,  int  fildes,  const  struct
       sockaddr *sock_addr, int sock_addr_size);
       void  explain_message_bind(char *message, int message_size, int fildes,
       const struct sockaddr *sock_addr, int sock_addr_size);
       void explain_message_errno_bind(char *message,  int  message_size,  int
       errnum,   int   fildes,   const   struct   sockaddr   *sock_addr,   int
       sock_addr_size);

DESCRIPTION

       These functions may be used to obtain explanations for errors  returned
       by the bind(2) system call.

   explain_bind
       const  char *explain_bind(int fildes, const struct sockaddr *sock_addr,
       int sock_addr_size);

       The explain_bind function is used to obtain an explanation of an  error
       returned  by  the  bind(2)  system  call.   The  least the message will
       contain is the value of strerror(errno), but usually it  will  do  much
       better, and indicate the underlying cause in more detail.

       The  errno global variable will be used to obtain the error value to be
       decoded.

       This function is intended to be  used  in  a  fashion  similar  to  the
       following example:
              if (bind(fildes, sock_addr, sock_addr_size) < 0)
              {
                  fprintf(stderr, "%s\n",
                      explain_bind(fildes, sock_addr, sock_addr_size));
                  exit(EXIT_FAILURE);
              }

       The   above   code   example   is   available   pre-packaged   as   the
       explain_bind_or_die(3) function.

       fildes  The original fildes, exactly as passed to  the  bind(2)  system
               call.

       sock_addr
               The original sock_addr, exactly as passed to the bind(2) system
               call.

       sock_addr_size
               The original sock_addr_size, exactly as passed to  the  bind(2)
               system call.

       Returns:
               The  message  explaining  the  error.   This  message buffer is
               shared by all libexplain functions which do not supply a buffer
               in  their  argument list.  This will be overwritten by the next
               call to any  libexplain  function  which  shares  this  buffer,
               including other threads.

       Note:  This  function  is  not  thread safe, because it shares a return
       buffer across all threads, and many other functions in this library.

   explain_errno_bind
       const char *explain_errno_bind(int errnum,  int  fildes,  const  struct
       sockaddr *sock_addr, int sock_addr_size);

       The  explain_errno_bind function is used to obtain an explanation of an
       error returned by the bind(2) system call.  The least the message  will
       contain  is  the value of strerror(errnum), but usually it will do much
       better, and indicate the underlying cause in more detail.

       This function is intended to be  used  in  a  fashion  similar  to  the
       following example:
              if (bind(fildes, sock_addr, sock_addr_size) < 0)
              {
                  int err = errno;
                  fprintf(stderr, "%s\n", explain_errno_bind(err,
                      fildes, sock_addr, sock_addr_size));
                  exit(EXIT_FAILURE);
              }

       The   above   code   example   is   available   pre-packaged   as   the
       explain_bind_or_die(3) function.

       errnum  The error value to be decoded, usually obtained from the  errno
               global  variable  just before this function is called.  This is
               necessary if you need to call any code between the system  call
               to  be explained and this function, because many libc functions
               will alter the value of errno.

       fildes  The original fildes, exactly as passed to  the  bind(2)  system
               call.

       sock_addr
               The original sock_addr, exactly as passed to the bind(2) system
               call.

       sock_addr_size
               The original sock_addr_size, exactly as passed to  the  bind(2)
               system call.

       Returns:
               The  message  explaining  the  error.   This  message buffer is
               shared by all libexplain functions which do not supply a buffer
               in  their  argument list.  This will be overwritten by the next
               call to any  libexplain  function  which  shares  this  buffer,
               including other threads.

       Note:  This  function  is  not  thread safe, because it shares a return
       buffer across all threads, and many other functions in this library.

   explain_message_bind
       void explain_message_bind(char *message, int message_size, int  fildes,
       const struct sockaddr *sock_addr, int sock_addr_size);

       The explain_message_bind function may be used to  obtain an explanation
       of an error returned by the bind(2) system call.  The least the message
       will  contain  is  the value of strerror(errno), but usually it will do
       much better, and indicate the underlying cause in more detail.

       The errno global variable will be used to obtain the error value to  be
       decoded.

       This  function  is  intended  to  be  used  in a fashion similar to the
       following example:
              if (bind(fildes, sock_addr, sock_addr_size) < 0)
              {
                  char message[3000];
                  explain_message_bind(message, sizeof(message),
                      fildes, sock_addr, sock_addr_size);
                  fprintf(stderr, "%s\n", message);
                  exit(EXIT_FAILURE);
              }

       The   above   code   example   is   available   pre-packaged   as   the
       explain_bind_or_die(3) function.

       message The  location  in  which  to  store the returned message.  If a
               suitable message return buffer is supplied,  this  function  is
               thread safe.

       message_size
               The  size  in  bytes  of  the  location  in  which to store the
               returned message.

       fildes  The original fildes, exactly as passed to  the  bind(2)  system
               call.

       sock_addr
               The original sock_addr, exactly as passed to the bind(2) system
               call.

       sock_addr_size
               The original sock_addr_size, exactly as passed to  the  bind(2)
               system call.

   explain_message_errno_bind
       void  explain_message_errno_bind(char  *message,  int message_size, int
       errnum,   int   fildes,   const   struct   sockaddr   *sock_addr,   int
       sock_addr_size);

       The  explain_message_errno_bind  function  may  be  used  to  obtain an
       explanation of an error returned by the bind(2) system call.  The least
       the  message will contain is the value of strerror(errnum), but usually
       it will do much better, and  indicate  the  underlying  cause  in  more
       detail.

       This  function  is  intended  to  be  used  in a fashion similar to the
       following example:
              if (bind(fildes, sock_addr, sock_addr_size) < 0)
              {
                  int err = errno;
                  char message[3000];
                  explain_message_errno_bind(message, sizeof(message), err,
                      fildes, sock_addr, sock_addr_size);
                  fprintf(stderr, "%s\n", message);
                  exit(EXIT_FAILURE);
              }

       The   above   code   example   is   available   pre-packaged   as   the
       explain_bind_or_die(3) function.

       message The  location  in  which  to  store the returned message.  If a
               suitable message return buffer is supplied,  this  function  is
               thread safe.

       message_size
               The  size  in  bytes  of  the  location  in  which to store the
               returned message.

       errnum  The error value to be decoded, usually obtained from the  errno
               global  variable  just before this function is called.  This is
               necessary if you need to call any code between the system  call
               to  be explained and this function, because many libc functions
               will alter the value of errno.

       fildes  The original fildes, exactly as passed to  the  bind(2)  system
               call.

       sock_addr
               The original sock_addr, exactly as passed to the bind(2) system
               call.

       sock_addr_size
               The original sock_addr_size, exactly as passed to  the  bind(2)
               system call.

SEE ALSO

       bind(2) bind a name to a socket

       explain_bind_or_die(3)
               bind a name to a socket and report errors

COPYRIGHT

       libexplain version 0.19
       Copyright (C) 2008 Peter Miller

                                                               explain_bind(3)