7.19.6.13 The vsprintf function

Synopsis

1

#include <stdarg.h>
#include <stdio.h>
int vsprintf(char * restrict s,
     const char * restrict format,
     va_list arg);

Description

2

The vsprintf function is equivalent to sprintf, with the variable argument list replaced by arg, which shall have been initialized by the va_start macro (and possibly subsequent va_arg calls). The vsprintf function does not invoke the va_end macro.[1] If copying takes place between objects that overlap, the behavior is undefined.

Returns

3

The vsprintf function returns the number of characters written in the array, not counting the terminating null character, or a negative value if an encoding error occurred.

Footnotes

[1]

As the functions vfprintf, vfscanf, vprintf, vscanf, vsnprintf, vsprintf, and vsscanf invoke the va_arg macro, the value of arg after the return is indeterminate.