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explain_opendir(3)	   Library Functions Manual	    explain_opendir(3)

NAME
       explain_opendir - explain opendir(3) errors

SYNOPSIS
       const char *explain_opendir(const char *pathname);
       const  char  *explain_errno_opendir(int	errnum,	const char *pathname);
       int errnum, const char *pathname);
       void explain_message_opendir(char *message, int message_size,
       void  explain_message_errno_opendir(char	 *message,  int	 message_size,
       const char *pathname);

DESCRIPTION
       These functions may be used to explain opendir(3) errors.

   explain_opendir
       const char *explain_opendir(const char *pathname);

       The explain_opendir function is used to obtain an explanation of	an er-
       ror returned by the opendir(3) function.	 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:
	      DIR *dp =	opendir(pathname);
	      if (!dp)
	      {
		  fprintf(stderr, "%s\n", explain_opendir(pathname));
		  exit(EXIT_FAILURE);
	      }

       pathname
	       The original pathname, exactly as passed	to the opendir(3) 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_opendir
       const char *explain_errno_opendir(int errnum,  const  char  *pathname);
       int errnum, const char *pathname);

       The  explain_errno_opendir function is used to obtain an	explanation of
       an error	returned by the	opendir(3) function.  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:
	      DIR *dp =	opendir(pathname);
	      if (!dp)
	      {
		  int errnum = errno;
		  const	char *message =	explain_errno_opendir(errnum, pathname);
		  fprintf(stderr, "%s\n", message);
		  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 opendir(3) 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_opendir
       void  explain_message_opendir(char  *message,  int  message_size, const
       char *pathname);

       The explain_message_opendir function is used to obtain  an  explanation
       of an error returned by the opendir(3) function.	 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:
	      DIR *dp =	opendir(pathname);
	      if (!dp)
	      {
		  char message[3000];
		  explain_message_opendir(message, sizeof(message), pathname);
		  fprintf(stderr, "%s\n", 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 if the buffer 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 opendir(3) sys-
	       tem call.

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

       The explain_message_errno_opendir function is used to obtain an	expla-
       nation  of an error returned by the opendir(3) function.	 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:
	      DIR *dp =	opendir(pathname);
	      if (!dp);
	      {
		  int err = errno;
		  char message[3000];
		  explain_message_errno_opendir(message, sizeof(message), err,
		      pathname);
		  fprintf(stderr, '%s\n', 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 if the buffer 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.

       pathname
	       The original pathname, exactly as passed	to the opendir(3) sys-
	       tem call.

COPYRIGHT
       libexplain version 1.3
       Copyright (C) 2008 Peter	Miller

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

							    explain_opendir(3)

NAME | SYNOPSIS | DESCRIPTION | COPYRIGHT | AUTHOR

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