explain_setbuffer_or_die(3) [debian man page]

explain_setbuffer_or_die(3)				     Library Functions Manual				       explain_setbuffer_or_die(3)

NAME

       explain_setbuffer_or_die - stream buffering operations and report errors

SYNOPSIS

       #include <libexplain/setbuffer.h>
       void explain_setbuffer_or_die(FILE *fp, char *data, size_t size);
       void explain_setbuffer_on_error(FILE *fp, char *data, size_t size);

DESCRIPTION

       The  explain_setbuffer_or_die  function	is used to call the setbuffer(3) system call. On failure an explanation will be printed to stderr,
       obtained from the explain_setbuffer(3) function, and then the process terminates by calling exit(EXIT_FAILURE).

       The explain_setbuffer_on_error function is used to call the setbuffer(3) system call. On failure an explanation will be printed to  stderr,
       obtained from the explain_setbuffer(3) function, but still returns to the caller.

       fp      The fp, exactly as to be passed to the setbuffer(3) system call.

       data    The data, exactly as to be passed to the setbuffer(3) system call.

       size    The size, exactly as to be passed to the setbuffer(3) system call.

RETURN VALUE

       The explain_setbuffer_or_die function only returns on success, see setbuffer(3) for more information. On failure, prints an explanation and
       exits, it does not return.

       The explain_setbuffer_on_error function always returns the value return by the wrapped setbuffer(3) system call.

EXAMPLE

       The explain_setbuffer_or_die function is intended to be used in a fashion similar to the following example:
	      void result = explain_setbuffer_or_die(fp, data, size);

SEE ALSO

       setbuffer(3)
	       stream buffering operations

       explain_setbuffer(3)
	       explain setbuffer(3) errors

       exit(2) terminate the calling process

COPYRIGHT

       libexplain version 0.52
       Copyright (C) 2010 Peter Miller

														       explain_setbuffer_or_die(3)

explain_setbuffer(3)					     Library Functions Manual					      explain_setbuffer(3)

NAME

       explain_setbuffer - explain setbuffer(3) errors

SYNOPSIS

       #include <libexplain/setbuffer.h>
       const char *explain_setbuffer(FILE *fp, char *data, size_t size);
       const char *explain_errno_setbuffer(int errnum, FILE *fp, char *data, size_t size);
       void explain_message_setbuffer(char *message, int message_size, FILE *fp, char *data, size_t size);
       void explain_message_errno_setbuffer(char *message, int message_size, int errnum, FILE *fp, char *data, size_t size);

DESCRIPTION

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

   explain_setbuffer
       const char *explain_setbuffer(FILE *fp, char *data, size_t size);

       The explain_setbuffer function is used to obtain an explanation of an error returned by the setbuffer(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.

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

       data    The original data, exactly as passed to the setbuffer(3) system call.

       size    The original size, exactly as passed to the setbuffer(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 buffer 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:
	      void result = setbuffer(fp, data, size);
	      if (result < 0)
	      {
		  fprintf(stderr, "%s
", explain_setbuffer(fp, data, size));
		  exit(EXIT_FAILURE);
	      }

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

   explain_errno_setbuffer
       const char *explain_errno_setbuffer(int errnum, FILE *fp, char *data, size_t size);

       The explain_errno_setbuffer function is used to obtain an explanation of an error returned by the setbuffer(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 neces-
	       sary 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 setbuffer(3) system call.

       data    The original data, exactly as passed to the setbuffer(3) system call.

       size    The original size, exactly as passed to the setbuffer(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 buffer 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:
	      void result = setbuffer(fp, data, size);
	      if (result < 0)
	      {
		  int err = errno;
		  fprintf(stderr, "%s
", explain_errno_setbuffer(err, fp, data, size));
		  exit(EXIT_FAILURE);
	      }

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

   explain_message_setbuffer
       void explain_message_setbuffer(char *message, int message_size, FILE *fp, char *data, size_t size);

       The  explain_message_setbuffer  function  is used to obtain an explanation of an error returned by the setbuffer(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 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 returned message.

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

       data    The original data, exactly as passed to the setbuffer(3) system call.

       size    The original size, exactly as passed to the setbuffer(3) system call.

       Example: This function is intended to be used in a fashion similar to the following example:
	      void result = setbuffer(fp, data, size);
	      if (result < 0)
	      {
		  char message[3000];
		  explain_message_setbuffer(message, sizeof(message), fp, data, size);
		  fprintf(stderr, "%s
", message);
		  exit(EXIT_FAILURE);
	      }

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

   explain_message_errno_setbuffer
       void explain_message_errno_setbuffer(char *message, int message_size, int errnum, FILE *fp, char *data, size_t size);

       The  explain_message_errno_setbuffer  function  is used to obtain an explanation of an error returned by the setbuffer(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 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 returned message.

       errnum  The  error value to be decoded, usually obtained from the errno global variable just before this function is called. This is neces-
	       sary 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 setbuffer(3) system call.

       data    The original data, exactly as passed to the setbuffer(3) system call.

       size    The original size, exactly as passed to the setbuffer(3) system call.

       Example: This function is intended to be used in a fashion similar to the following example:
	      void result = setbuffer(fp, data, size);
	      if (result < 0)
	      {
		  int err = errno;
		  char message[3000];
		  explain_message_errno_setbuffer(message, sizeof(message), err, fp, data, size);
		  fprintf(stderr, "%s
", message);
		  exit(EXIT_FAILURE);
	      }

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

SEE ALSO

       setbuffer(3)
	       stream buffering operations

       explain_setbuffer_or_die(3)
	       stream buffering operations and report errors

COPYRIGHT

       libexplain version 0.52
       Copyright (C) 2010 Peter Miller

															      explain_setbuffer(3)