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explain_getchar(3)	   Library Functions Manual	    explain_getchar(3)

NAME
       explain_getchar - explain getchar(3) errors

SYNOPSIS
       #include	<libexplain/getchar.h>
       const char *explain_getchar(void);
       const char *explain_errno_getchar(int errnum, void);
       void explain_message_getchar(char *message, int message_size);
       void explain_message_errno_getchar(char *message, int message_size, int
       errnum);

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

   explain_getchar
       const char *explain_getchar(void);

       The explain_getchar function is used to obtain an explanation of	an er-
       ror returned by the getchar(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:
	      int c = getchar();
	      if (c == EOF && ferror(stdin))
	      {
		  fprintf(stderr, "%s\n", explain_getchar());
		  exit(EXIT_FAILURE);
	      }

       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_getchar
       const char *explain_errno_getchar(int errnum);

       The  explain_errno_getchar function is used to obtain an	explanation of
       an error	returned by the	getchar(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:
	      int c = getchar();
	      if (c == EOF && ferror(stdin))
	      {
		  int err = errno;
		  fprintf(stderr, "%s\n", explain_errno_getchar(err, ));
		  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.

       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_getchar
       void explain_message_getchar(char *message, int message_size);

       The explain_message_getchar function may	be used	to  obtain an explana-
       tion of an error	returned by the	getchar(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:
	      int c = getchar();
	      if (c == EOF && ferror(stdin))
	      {
		  char message[3000];
		  explain_message_getchar(message, sizeof(message), );
		  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.

   explain_message_errno_getchar
       void explain_message_errno_getchar(char *message, int message_size, int
       errnum);

       The explain_message_errno_getchar function may be used to obtain	an ex-
       planation of an error returned by  the  getchar(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:
	      int c = getchar();
	      if (c == EOF && ferror(stdin))
	      {
		  int err = errno;
		  char message[3000];
		  explain_message_errno_getchar(message, sizeof(message), err, );
		  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.

SEE ALSO
       getchar(3)
	       input of	characters

       explain_getchar_or_die(3)
	       input of	characters and report errors

COPYRIGHT
       libexplain version 1.3
       Copyright (C) 2008 Peter	Miller

							    explain_getchar(3)

NAME | SYNOPSIS | DESCRIPTION | SEE ALSO | COPYRIGHT

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