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explain_unlink(3)	   Library Functions Manual	     explain_unlink(3)

NAME
       explain_unlink -	explain	unlink(2) errors

SYNOPSIS
       #include	<libexplain/unlink.h>
       const char *explain_unlink(const	char *pathname);
       void explain_message_unlink(char	*message, int message_size, const char
       *pathname);
       const char *explain_errno_unlink(int errnum, const char *pathname);
       void explain_message_errno_unlink(char *message,	int message_size,  int
       errnum, const char *pathname);

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

   explain_unlink
       const char *explain_unlink(const	char *pathname);

       The explain_unlink function is used to obtain an	explanation of an  er-
       ror  returned by	the unlink(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 (unlink(pathname) < 0)
	      {
		  fprintf(stderr, '%s0,	explain_unlink(pathname));
		  exit(EXIT_FAILURE);
	      }

       pathname
	       The  original pathname, exactly as passed to the	unlink(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_unlink
       const char *explain_errno_unlink(int errnum, const char * pathname);

       The  explain_errno_unlink  function is used to obtain an	explanation of
       an error	returned by the	unlink(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 (unlink(pathname) < 0)
	      {
		  int err = errno;
		  fprintf(stderr, '%s0,	explain_errno_unlink(err, pathname));
		  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.

       pathname
	       The  original pathname, exactly as passed to the	unlink(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_unlink
       void explain_message_unlink(char	*message, int message_size, const char
       *pathname);

       The explain_message_unlink function is used to obtain an	explanation of
       an  error returned by the unlink(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 (unlink(pathname) < 0)
	      {
		  char message[3000];
		  explain_message_unlink(message, sizeof(message), pathname);
		  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.

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

   explain_message_errno_unlink
       void  explain_message_errno_unlink(char *message, int message_size, int
       errnum, const char *pathname);

       The explain_message_errno_unlink	function is used to obtain an explana-
       tion  of	an error returned by the unlink(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 (unlink(pathname) < 0)
	      {
		  int err = errno;
		  char message[3000];
		  explain_message_errno_unlink(message,	sizeof(message), err,
		      pathname);
		  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.

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

COPYRIGHT
       libexplain version 1.3
       Copyright (C) 2008 Peter	Miller

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

							     explain_unlink(3)

NAME | SYNOPSIS | DESCRIPTION | COPYRIGHT | AUTHOR

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