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explain_symlink(3)	   Library Functions Manual	    explain_symlink(3)

NAME
       explain_symlink - explain symlink(2) errors

SYNOPSIS
       #include	<libexplain/symlink.h>
       const char *explain_symlink(const char *oldpath,	const char *newpath);
       const  char  *explain_errno_symlink(int	errnum,	 const	char *oldpath,
       const char *newpath);
       void explain_message_symlink(char  *message,  int  message_size,	 const
       char *oldpath, const char *newpath);
       void explain_message_errno_symlink(char *message, int message_size, int
       errnum, const char *oldpath, const char *newpath);

DESCRIPTION
       These functions may be used to obtain explanations for  symlink(2)  er-
       rors.

   explain_symlink
       const char *explain_symlink(const char *oldpath,	const char *newpath);

       The explain_symlink function is used to obtain an explanation of	an er-
       ror returned by the symlink(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:
	      if (symlink(oldpath, rewpath) < 0)
	      {
		  fprintf(stderr, '%s0,	explain_symlink(oldpath, newpath));
		  exit(EXIT_FAILURE);
	      }

       oldpath The original oldpath, exactly as	passed to the symlink(2)  sys-
	       tem call.

       newpath The  original newpath, exactly as passed	to the symlink(2) sys-
	       tem 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, in-
	       cluding 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_symlink
       const  char  *explain_errno_symlink(int	errnum,	 const	char *oldpath,
       const char * newpath);

       The explain_errno_symlink function is used to obtain an explanation  of
       an error	returned by the	symlink(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:
	      if (symlink(oldpath, newpath) < 0)
	      {
		  int err = errno;
		  fprintf(stderr, '%s0,	explain_errno_symlink(err, oldpath,
		      newpath));
		  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.

       oldpath The original oldpath, exactly as	passed to the symlink(2)  sys-
	       tem call.

       newpath The  original newpath, exactly as passed	to the symlink(2) sys-
	       tem 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, in-
	       cluding 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_symlink
       void  explain_message_symlink(char  *message,  int  message_size, const
       char *oldpath, const char *newpath);

       The explain_message_symlink function is used to obtain  an  explanation
       of an error returned by the symlink(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]fP 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:
	      if (symlink(oldpath, newpath) < 0)
	      {
		  char message[3000];
		  explain_message_symlink(message, sizeof(message), oldpath,
		      newpath);
		  fprintf(stderr, '%s0,	message);
		  exit(EXIT_FAILURE);
	      }

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

       message_size
	       The  size  in  bytes  of	the location in	which to store the re-
	       turned message.

       oldpath The original oldpath, exactly as	passed to the symlink(2)  sys-
	       tem call.

       newpath The  original newpath, exactly as passed	to the symlink(2) sys-
	       tem call.

   explain_message_errno_symlink
       void explain_message_errno_symlink(char *message, int message_size, int
       errnum, const char *oldpath, const char *newpath);

       The  explain_message_errno_symlink function is used to obtain an	expla-
       nation of an error returned by the symlink(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  de-
       tail.

       This  function  is intended to be used in a fashion similar to the fol-
       lowing example:

       if (symlink(oldpath, newpath) < 0)
       {
	   int err = errno;
	   char	message[3000];
	   explain_message_errno_symlink(message, sizeof(message), err,
	       oldpath,	newpath);
	   fprintf(stderr, '%s0, message);
	   exit(EXIT_FAILURE);
       }

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

       message_size
	       The size	in bytes of the	location in which  to  store  the  re-
	       turned 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.

       oldpath The  original oldpath, exactly as passed	to the symlink(2) sys-
	       tem call.

       newpath The original newpath, exactly as	passed to the symlink(2)  sys-
	       tem call.

COPYRIGHT
       libexplain version 1.3
       Copyright (C) 2008 Peter	Miller

AUTHOR
       Written by Peter	Miller <pmiller@opensource.org.au>

							    explain_symlink(3)

NAME | SYNOPSIS | DESCRIPTION | COPYRIGHT | AUTHOR

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