posix man page for vfprintf

VFPRINTF(3P)						     POSIX Programmer's Manual						      VFPRINTF(3P)

PROLOG
       This  manual page is part of the POSIX Programmer's Manual.  The Linux implementation of this interface may differ (consult the correspond-
       ing Linux manual page for details of Linux behavior), or the interface may not be implemented on Linux.

NAME
       vdprintf, vfprintf, vprintf, vsnprintf, vsprintf -- format output of a stdarg argument list

SYNOPSIS
       #include <stdarg.h>
       #include <stdio.h>

       int vdprintf(int fildes, const char *restrict format, va_list ap);
       int vfprintf(FILE *restrict stream, const char *restrict format,
	   va_list ap);
       int vprintf(const char *restrict format, va_list ap);
       int vsnprintf(char *restrict s, size_t n, const char *restrict format,
	   va_list ap);
       int vsprintf(char *restrict s, const char *restrict format, va_list ap);

DESCRIPTION
       The functionality described on this reference page is aligned with the ISO C standard. Any conflict between the requirements described here
       and the ISO C standard is unintentional. This volume of POSIX.1-2008 defers to the ISO C standard.

       The  vdprintf(),  vfprintf(),  vprintf(), vsnprintf(), and vsprintf() functions shall be equivalent to the  dprintf(), fprintf(), printf(),
       snprintf(), and sprintf() functions respectively, except that instead of being called with a variable number of arguments, they are  called
       with an argument list as defined by <stdarg.h>.

       These functions shall not invoke the va_end macro. As these functions invoke the va_arg macro, the value of ap after the return is unspeci-
       fied.

RETURN VALUE
       Refer to fprintf().

ERRORS
       Refer to fprintf().

       The following sections are informative.

EXAMPLES
       None.

APPLICATION USAGE
       Applications using these functions should call va_end(ap) afterwards to clean up.

RATIONALE
       None.

FUTURE DIRECTIONS
       None.

SEE ALSO
       Section 2.5, Standard I/O Streams, fprintf()

       The Base Definitions volume of POSIX.1-2008, <stdarg.h>, <stdio.h>

COPYRIGHT
       Portions of this text are reprinted and reproduced in electronic form from IEEE Std 1003.1, 2013 Edition, Standard for Information Technol-
       ogy  --	Portable  Operating  System  Interface (POSIX), The Open Group Base Specifications Issue 7, Copyright (C) 2013 by the Institute of
       Electrical and Electronics Engineers, Inc and The Open Group.  (This is POSIX.1-2008 with the 2013 Technical Corrigendum 1 applied.) In the
       event of any discrepancy between this version and the original IEEE and The Open Group Standard, the original IEEE and The Open Group Stan-
       dard is the referee document. The original Standard can be obtained online at http://www.unix.org/online.html .

       Any typographical or formatting errors that appear in this page are most likely to have been introduced during the conversion of the source
       files to man page format. To report such errors, see https://www.kernel.org/doc/man-pages/reporting_bugs.html .

IEEE
/The Open Group						       2013							      VFPRINTF(3P)