ref: f3dc7e55ab7f4b5f7c06d546ae59fc446b45bc6d
dir: /sys/src/cmd/unix/drawterm/libc/fmtstr.c/
#include <u.h>
#include <libc.h>
#include "fmtdef.h"
char*
fmtstrflush(Fmt *f)
{
if(f->start == nil)
return nil;
*(char*)f->to = '\0';
return (char*)f->start;
}