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explain_pclose(3)	   Library Functions Manual	     explain_pclose(3)

NAME
       explain_pclose -	explain	pclose(3) errors

SYNOPSIS
       #include	<libexplain/pclose.h>
       const char *explain_pclose(FILE *fp);
       const char *explain_errno_pclose(int errnum, FILE *fp);
       void explain_message_pclose(char	*message, int message_size, FILE *fp);
       void  explain_message_errno_pclose(char *message, int message_size, int
       errnum, FILE *fp);

DESCRIPTION
       These functions may be used to obtain explanations for errors  returned
       by the pclose(3)	system call.

   explain_pclose
       const char *explain_pclose(FILE *fp);

       The  explain_pclose function is used to obtain an explanation of	an er-
       ror returned by the pclose(3) 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 (pclose(fp) < 0)
	      {
		  fprintf(stderr, "%s\n", explain_pclose(fp));
		  exit(EXIT_FAILURE);
	      }

       The  above  code	 example  is  available	 pre-packaged	as   the   ex-
       plain_pclose_or_die(3) function.

       fp      The  original  fp,  exactly  as	passed to the pclose(3)	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_pclose
       const char *explain_errno_pclose(int errnum, FILE *fp);

       The  explain_errno_pclose  function is used to obtain an	explanation of
       an error	returned by the	pclose(3) 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 (pclose(fp) < 0)
	      {
		  int err = errno;
		  fprintf(stderr, "%s\n", explain_errno_pclose(err, fp));
		  exit(EXIT_FAILURE);
	      }

       The   above   code   example  is	 available  pre-packaged  as  the  ex-
       plain_pclose_or_die(3) function.

       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.

       fp      The original fp,	exactly	as  passed  to	the  pclose(3)	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_pclose
       void explain_message_pclose(char	*message, int message_size, FILE *fp);

       The explain_message_pclose function may be used to  obtain an  explana-
       tion  of	an error returned by the pclose(3) 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 (pclose(fp) < 0)
	      {
		  char message[3000];
		  explain_message_pclose(message, sizeof(message), fp);
		  fprintf(stderr, "%s\n", message);
		  exit(EXIT_FAILURE);
	      }

       The   above   code   example  is	 available  pre-packaged  as  the  ex-
       plain_pclose_or_die(3) function.

       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.

       fp      The  original  fp,  exactly  as	passed to the pclose(3)	system
	       call.

   explain_message_errno_pclose
       void explain_message_errno_pclose(char *message,	int message_size,  int
       errnum, FILE *fp);

       The  explain_message_errno_pclose function may be used to obtain	an ex-
       planation of an error returned by the pclose(3) 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  de-
       tail.

       This  function  is intended to be used in a fashion similar to the fol-
       lowing example:
	      if (pclose(fp) < 0)
	      {
		  int err = errno;
		  char message[3000];
		  explain_message_errno_pclose(message,	sizeof(message), err, fp);
		  fprintf(stderr, "%s\n", message);
		  exit(EXIT_FAILURE);
	      }

       The  above  code	 example  is  available	 pre-packaged	as   the   ex-
       plain_pclose_or_die(3) function.

       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.

       fp      The original fp,	exactly	as  passed  to	the  pclose(3)	system
	       call.

SEE ALSO
       pclose(3)
	       process I/O

       explain_pclose_or_die(3)
	       process I/O and report errors

COPYRIGHT
       libexplain version 1.3
       Copyright (C) 2009 Peter	Miller

							     explain_pclose(3)

NAME | SYNOPSIS | DESCRIPTION | SEE ALSO | COPYRIGHT

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