man vscanf () - format input of a stdarg argument list
NAME
vfscanf, vscanf, vsscanf - format input of a stdarg argument list
SYNOPSIS
#include <stdarg.h>
#include <stdio.h>
int vfscanf(FILE *restrict stream, const char *restrict
format,
va_list arg);
int vscanf(const char *restrict format, va_list arg);
int vsscanf(const char *restrict s, const char *restrict
format,
va_list arg);
DESCRIPTION
The vscanf(), vfscanf(), and vsscanf() functions shall be equivalent to the scanf(), fscanf(), and sscanf() functions, respectively, except that instead of being called with a variable number of arguments, they are called with an argument list as defined in the <stdarg.h> header. 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 unspecified.
RETURN VALUE
Refer to fscanf() .
ERRORS
Refer to fscanf() .
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
fscanf() , the Base Definitions volume of IEEE Std 1003.1-2001, <stdarg.h>, <stdio.h>
COPYRIGHT
Portions of this text are reprinted and reproduced in electronic form from IEEE Std 1003.1, 2003 Edition, Standard for Information Technology -- Portable Operating System Interface (POSIX), The Open Group Base Specifications Issue 6, Copyright (C) 2001-2003 by the Institute of Electrical and Electronics Engineers, Inc and The Open Group. 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 Standard is the referee document. The original Standard can be obtained online at http://www.opengroup.org/unix/online.html .