Content-type: text/html Man page of vprintf

vprintf

Section: C Library Functions (3)
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NAME

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

STANDARDS

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

vfprintf(), vprintf(), 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 specifications, 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.  

DESCRIPTION

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

These functions are the same as the printf(), fprintf(), and sprintf() functions, respectively, except that these functions are not called with a variable number of parameters. Instead, vprintf(), vfprintf(), 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


 

Index

NAME
LIBRARY
SYNOPSIS
STANDARDS
PARAMETERS
DESCRIPTION
EXAMPLES
RELATED INFORMATION

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Time: 02:41:47 GMT, October 02, 2010