__vfprintf_chk -- convert formatted output, with stack checking


#include <libc.h>

int __vfprintf_chk(FILE * fp, int flag, const char * format, va_list ap);


The interface __vfprintf_chk() shall function in the same way as the interface vfprintf(), except that __vfprintf_chk() shall check for stack overflow before computing a result, depending on the value of the flag parameter. If an overflow is anticipated, the function shall abort and the program calling it shall exit.

In general, the higher the value of flag, the more security measures this interface shall take in the form of checking the stack, parameter values, and so on.

The __vfprintf_chk() function is not in the source standard; it is only in the binary standard.