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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 buf-
       fer 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 buf-
       fer 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)

NAME | SYNOPSIS | DESCRIPTION | SEE ALSO | COPYRIGHT

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