vprintf() - I/O Function

vprintf() is an I/O function that writes the contents of the format string to the stdout with a pointer to a list of arguments replacing the argument list. The total number of characters are returned by this function, but on failure a negative number is returned.

Syntax:

The following table lists the type specifier used with vprintf()

Type	Description
c	Character
d or i	Signed decimal integer
e	Scientific notation using e character
E	Scientific notation using E character
f	Decimal floating point
g	Use the shorter of %e or %f
G	Use the shorter of %E or %f
o	Signed octal
s	String of characters
u	Unsigned decimal integer
x	Unsigned hexadecimal integer
X	Unsigned hexadecimal integer(capital)
p	Pointer address
%	A % followed by another % character will write % to the stream.

Example :

#include <stdio.h> #include <stdarg.h> void Form (char * format, ...) { va_list args; va_start (args, format); vprintf (format, args); va_end (args); } int main () { Form ("Function with %d variable argument.\n",1); Form ("Function with %d variable %s.\n",2,"arguments"); return 0; }

Result :
In the above example vprintf() is used to call a function with different number of arguments.