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explain_getsockname(3)	   Library Functions Manual	explain_getsockname(3)

NAME
       explain_getsockname - explain getsockname(2) errors

SYNOPSIS
       #include	<libexplain/getsockname.h>
       const char *explain_getsockname(int fildes, struct sockaddr *sock_addr,
       socklen_t *sock_addr_size);
       const char *explain_errno_getsockname(int errnum,  int  fildes,	struct
       sockaddr	*sock_addr, socklen_t *sock_addr_size);
       void  explain_message_getsockname(char  *message, int message_size, int
       fildes, struct sockaddr *sock_addr, socklen_t *sock_addr_size);
       void explain_message_errno_getsockname(char *message, int message_size,
       int   errnum,   int   fildes,  struct  sockaddr	*sock_addr,  socklen_t
       *sock_addr_size);

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

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

       The explain_getsockname function	is used	to obtain an explanation of an
       error  returned	by the getsockname(2) system call.  The	least the mes-
       sage 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  fol-
       lowing example:
	      struct sockaddr sock_addr;
	      socklen_t	sock_addr_size = sizeof(sock_addr);
	      if (getsockname(fildes, &sock_addr, &sock_addr_size) < 0)
	      {
		  fprintf(stderr, "%s\n", explain_getsockname(fildes,
		      &sock_addr, &sock_addr_size));
		  exit(EXIT_FAILURE);
	      }

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

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

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

       sock_addr_size
	       The original sock_addr_size, exactly as passed to the  getsock-
	       name(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 buf-
       fer across all threads, and many	other functions	in this	library.

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

       The explain_errno_getsockname function is used to obtain	an explanation
       of an error returned by the getsockname(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  fol-
       lowing example:
	      struct sockaddr sock_addr;
	      socklen_t	sock_addr_size = sizeof(sock_addr);
	      if (getsockname(fildes, &sock_addr, &sock_addr_size) < 0)
	      {
		  int err = errno;
		  fprintf(stderr, "%s\n", explain_errno_getsockname(err,
		      fildes, &sock_addr, &sock_addr_size));
		  exit(EXIT_FAILURE);
	      }

       The  above  code	 example is available pre-packaged as the explain_get-
       sockname_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	getsockname(2)
	       system call.

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

       sock_addr_size
	       The original sock_addr_size, exactly as passed to the  getsock-
	       name(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 buf-
       fer across all threads, and many	other functions	in this	library.

   explain_message_getsockname
       void explain_message_getsockname(char *message, int  message_size,  int
       fildes, struct sockaddr *sock_addr, socklen_t *sock_addr_size);

       The  explain_message_getsockname	 function  may	be  used to  obtain an
       explanation of an error returned	by  the	 getsockname(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  fol-
       lowing example:
	      struct sockaddr sock_addr;
	      socklen_t	sock_addr_size = sizeof(sock_addr);
	      if (getsockname(fildes, &sock_addr, &sock_addr_size) < 0)
	      {
		  char message[3000];
		  explain_message_getsockname(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_get-
       sockname_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	getsockname(2)
	       system call.

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

       sock_addr_size
	       The  original sock_addr_size, exactly as	passed to the getsock-
	       name(2) system call.

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

       The explain_message_errno_getsockname function may be used to obtain an
       explanation  of	an  error  returned by the getsockname(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  fol-
       lowing example:
	      struct sockaddr sock_addr;
	      socklen_t	sock_addr_size = sizeof(sock_addr);
	      if (getsockname(fildes, &sock_addr, &sock_addr_size) < 0)
	      {
		  int err = errno;
		  char message[3000];
		  explain_message_errno_getsockname(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_get-
       sockname_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	getsockname(2)
	       system call.

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

       sock_addr_size
	       The  original sock_addr_size, exactly as	passed to the getsock-
	       name(2) system call.

SEE ALSO
       getsockname(2)
	       get socket name

       explain_getsockname_or_die(3)
	       get socket name and report errors

COPYRIGHT
       libexplain version 1.3
       Copyright (C) 2009 Peter	Miller

							explain_getsockname(3)

NAME | SYNOPSIS | DESCRIPTION | SEE ALSO | COPYRIGHT

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