vprintf(3)						     Library Functions Manual							vprintf(3)

NAME

       vprintf, vfprintf, vsnprintf, vsprintf - Format a variable number of parameters for output

LIBRARY

       Standard C Library (libc.so, libc.a)

SYNOPSIS

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

       int vprintf(
	       const char *format,
	       va_list printarg);

       int vfprintf(
	       FILE *stream,
	       const char *format,
	       va_list printarg);

       int vsnprintf(
	       char *string, size_t n,
	       const char *format,
	       va_list printarg);

       int vsprintf(
	       char *string,
	       const char *format,
	       va_list printarg);

STANDARDS

       Interfaces documented on this reference page conform to industry standards as follows:

       vfprintf(), vprintf(), vsnprintf(), vsprintf():	ISO C, XPG4, XPG4-UNIX

       Refer to the standards(5) reference page for more information about industry standards and associated tags.

PARAMETERS

       Specifies a character string that contains two types of objects: Plain characters, which are copied to the output stream.  Conversion spec-
       ifications, each of which causes zero or more items to be fetched from the stdarg parameter lists.  Specifies the arguments to be  printed.
       Specifies the output stream.  Specifies the buffer to which output is printed.  Specifies the size of the buffer referred to by string.

DESCRIPTION

       The vprintf(), vfprintf(), vsnprintf(), and vsprintf() functions format and write stdarg parameter lists.

       These functions are the same as the printf(), fprintf(), snprintf(), and sprintf() functions, respectively, except that these functions are
       not called with a variable number of parameters.  Instead, vprintf(), vfprintf(), vsnprintf(), and vsprintf() are called with  a  parameter
       list  pointer as defined by stdarg.  Because these functions invoke the va_arg() macro and not the va_end() macro, the value of printarg is
       indeterminate after a return.  Therefore, applications should execute a call to the va_end() macro after a call to one of these functions.

EXAMPLES

       The following example demonstrates how the vfprintf() function can be used to write an error routine:

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

       void    error(char *funct, char *fmt, ...)  {
	       va_list args;
	       /*
	       ** Display the name of the function that called error
	       */
	       fprintf(stderr, "ERROR in %s: ", funct);
	       /*
	       ** Display the remainder of the message
	       */
	       va_start(args, fmt);
	       vfprintf(stderr, fmt, args);
	       va_end(args);
	       abort(); }

RELATED INFORMATION

       Functions: fopen(3), printf(3), vwprintf(3), wprintf(3) delim off

																	vprintf(3)