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explain_puts(3)		   Library Functions Manual	       explain_puts(3)

NAME
       explain_puts - explain puts(3) errors

SYNOPSIS
       #include	<libexplain/puts.h>
       const char *explain_puts(const char *s);
       const char *explain_errno_puts(int errnum, const	char *s);
       void explain_message_puts(char *message,	int message_size, const	char
       *s);
       void explain_message_errno_puts(char *message, int message_size,	int
       errnum, const char *s);

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

   explain_puts
       const char *explain_puts(const char *s);

       The explain_puts	function is used to obtain an explanation of an	 error
       returned	by the puts(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.

       s       The original s, exactly as passed to the	puts(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, including
	       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.

       Example:	 This  function	is intended to be used in a fashion similar to
       the following example:
	      if (puts(s) < 0)
	      {
		  fprintf(stderr, "%s\n", explain_puts(s));
		  exit(EXIT_FAILURE);
	      }

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

   explain_errno_puts
       const char *explain_errno_puts(int errnum, const	char *s);

       The  explain_errno_puts function	is used	to obtain an explanation of an
       error returned by the puts(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.

       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.

       s       The original s, exactly as passed to the	puts(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, including
	       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.

       Example:	 This  function	is intended to be used in a fashion similar to
       the following example:
	      if (puts(s) < 0)
	      {
		  int err = errno;
		  fprintf(stderr, "%s\n", explain_errno_puts(err, s));
		  exit(EXIT_FAILURE);
	      }

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

   explain_message_puts
       void explain_message_puts(char *message,	int message_size, const	char
       *s);

       The explain_message_puts	function is used to obtain an  explanation  of
       an  error  returned  by	the puts(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.

       message The location in which to	store the returned message. If a suit-
	       able 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.

       s       The original s, exactly as passed to the	puts(3)	system call.

       Example:	 This  function	is intended to be used in a fashion similar to
       the following example:
	      if (puts(s) < 0)
	      {
		  char message[3000];
		  explain_message_puts(message,	sizeof(message), s);
		  fprintf(stderr, "%s\n", message);
		  exit(EXIT_FAILURE);
	      }

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

   explain_message_errno_puts
       void explain_message_errno_puts(char *message, int message_size,	int
       errnum, const char *s);

       The explain_message_errno_puts function is used to obtain  an  explana-
       tion  of	 an  error  returned by	the puts(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.

       message The location in which to	store the returned message. If a suit-
	       able 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.

       s       The original s, exactly as passed to the	puts(3)	system call.

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

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

SEE ALSO
       puts(3) write a string and a trailing newline to	stdout

       explain_puts_or_die(3)
	       write  a	string and a trailing newline to stdout	and report er-
	       rors

COPYRIGHT
       libexplain version 1.3
       Copyright (C) 2009 Peter	Miller

							       explain_puts(3)

NAME | SYNOPSIS | DESCRIPTION | SEE ALSO | COPYRIGHT

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