Provided by: libexplain-dev_1.4.D001-12_amd64 bug

NAME

       explain_socket - explain socket(2) errors

SYNOPSIS

       #include <libexplain/socket.h>
       const char *explain_socket(int domain, int type, int protocol);
       const char *explain_errno_socket(int errnum, int domain, int type, int protocol);
       void  explain_message_socket(char  *message,  int  message_size, int domain, int type, int
       protocol);
       void explain_message_errno_socket(char *message, int message_size, int errnum, int domain,
       int type, int protocol);

DESCRIPTION

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

   explain_socket
       const char *explain_socket(int domain, int type, int protocol);

       The explain_socket function is used to obtain an explanation of an error returned  by  the
       socket(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 (socket(domain, type, protocol) < 0)
              {
                  fprintf(stderr, "%s\n", explain_socket(domain, type, protocol));
                  exit(EXIT_FAILURE);
              }

       domain  The original domain, exactly as passed to the socket(2) system call.

       type    The original type, exactly as passed to the socket(2) system call.

       protocol
               The original protocol, exactly as passed to the socket(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_socket
       const char *explain_errno_socket(int errnum, int domain, int type, int protocol);

       The explain_errno_socket function is used to obtain an explanation of an error returned by
       the socket(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 (socket(domain, type, protocol) < 0)
              {
                  int err = errno;
                  fprintf(stderr, "%s\n", explain_errno_socket(err,
                      domain, type, protocol));
                  exit(EXIT_FAILURE);
              }

       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.

       domain  The original domain, exactly as passed to the socket(2) system call.

       type    The original type, exactly as passed to the socket(2) system call.

       protocol
               The original protocol, exactly as passed to the socket(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_socket
       void  explain_message_socket(char  *message,  int  message_size, int domain, int type, int
       protocol);

       The explain_message_socket function may be used to  obtain  an  explanation  of  an  error
       returned by the socket(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 (socket(domain, type, protocol) < 0)
              {
                  char message[3000];
                  explain_message_socket(message, sizeof(message), domain, type, protocol);
                  fprintf(stderr, "%s\n", message);
                  exit(EXIT_FAILURE);
              }

       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.

       domain  The original domain, exactly as passed to the socket(2) system call.

       type    The original type, exactly as passed to the socket(2) system call.

       protocol
               The original protocol, exactly as passed to the socket(2) system call.

   explain_message_errno_socket
       void explain_message_errno_socket(char *message, int message_size, int errnum, int domain,
       int type, int protocol);

       The explain_message_errno_socket function may be used to obtain an explanation of an error
       returned by the socket(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 (socket(domain, type, protocol) < 0)
              {
                  int err = errno;
                  char message[3000];
                  explain_message_errno_socket(message, sizeof(message), err,
                      domain, type, protocol);
                  fprintf(stderr, "%s\n", message);
                  exit(EXIT_FAILURE);
              }

       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.

       domain  The original domain, exactly as passed to the socket(2) system call.

       type    The original type, exactly as passed to the socket(2) system call.

       protocol
               The original protocol, exactly as passed to the socket(2) system call.

SEE ALSO

       socket(2)
               create an endpoint for communication

       explain_socket_or_die(3)
               create an endpoint for communication and report errors

COPYRIGHT

       libexplain version 1.4
       Copyright (C) 2008 Peter Miller

                                                                                explain_socket(3)