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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  er-
     rnum, const char *pathname);

DESCRIPTION
     These functions may be used to obtain explanations for unlink(2) errors.

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

     The  explain_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  de-
     coded.

     This  function is intended to be used in a fashion similar to the following
     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)  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 ar-
	     gument list.  This will be overwritten by the next call to any lib-
	     explain 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_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 bet-
     ter, and indicate the underlying cause in more detail.

     This function is intended to be used in a fashion similar to the  following
     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  nec-
	     essary  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)  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 ar-
	     gument list.  This will be overwritten by the next call to any lib-
	     explain 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_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  bet-
     ter, and indicate the underlying cause in more detail.

     The  errno global variable will be used to obtain the error value to be de-
     coded.

     This function is intended to be used in a fashion similar to the  following
     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 returned
	     message.

     pathname
	     The original pathname, exactly as passed to  the  unlink(2)  system
	     call.

   explain_message_errno_unlink
     void  explain_message_errno_unlink(char *message, int message_size, int er-
     rnum, const char *pathname);

     The explain_message_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 following
     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	returned
	     message.

     errnum  The  error  value	to  be	decoded, usually obtained from the errno
	     global variable just before this function is called.  This is  nec-
	     essary  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)  system
	     call.

COPYRIGHT
     libexplain version 1.3
     Copyright (C) 2008 Peter Miller

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

							       explain_unlink(3)

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