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explain_close(3)	   Library Functions Manual	      explain_close(3)

NAME
       explain_close - explain close(2)	errors

SYNOPSIS
       #include	<libexplain/close.h>
       const char *explain_close(int fildes);
       const char *explain_errno_close(int errnum, int fildes);
       void   explain_message_close(char   *message,   int  message_size,  int
       fildes);
       void explain_message_errno_close(char *message, int  message_size,  int
       errnum, int fildes);

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

   explain_close
       const char *explain_close(int fildes);

       The explain_close function is used to obtain an explanation of an error
       returned	by the close(2)	system call.  The least	the message will  con-
       tain  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
       decoded.

       This  function  is intended to be used in a fashion similar to the fol-
       lowing example:
	      if (close(fildes)	< 0)
	      {
		  fprintf(stderr, "%s\n", explain_close(fildes));
		  exit(EXIT_FAILURE);
	      }

       fildes  The original fildes, exactly as passed to the  close(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, in-
	       cluding 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_close
       const char *explain_errno_close(int errnum, int fildes);

       The explain_errno_close function	is used	to obtain an explanation of an
       error returned by the close(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 (close(fildes)	< 0)
	      {
		  int err = errno;
		  fprintf(stderr, "%s\n", explain_close(err, fildes));
		  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.

       fildes  The  original  fildes, exactly as passed	to the close(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,  in-
	       cluding 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_close
       void  explain_message_close(char	 *message,   int   message_size,   int
       fildes);

       The  explain_message_close function is used to obtain an	explanation of
       an error	returned by the	close(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 (close(fildes)	< 0)
	      {
		  char message[3000];
		  explain_message_close(message, sizeof(message), fildes);
		  fprintf(stderr, "%s\n", message);
		  exit(EXIT_FAILURE);
	      }

       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  re-
	       turned message.

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

   explain_message_errno_close
       void explain_message_errno_close(char *message, int  message_size,  int
       errnum, int fildes);

       The  explain_message_errno_close	function is used to obtain an explana-
       tion of an error	returned by the	close(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 (close(fildes)	< 0)
	      {
		  int err = errno;
		  char message[3000];
		  explain_message_errno_close(message, sizeof(message),	err, fildes);
		  fprintf(stderr, "%s\n", message);
		  exit(EXIT_FAILURE);
	      }

       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 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.

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

SEE ALSO
       close   close a file descriptor

       explain_close_or_die
	       close a file descriptor and report errors

COPYRIGHT
       libexplain version 1.3
       Copyright (C) 2008 Peter	Miller

							      explain_close(3)

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