git: 9front

ref: 41ca874b7b2ba5d588ea1a25f639d3e46d48cc99
dir: /sys/src/libstdio/ftello.c/

View raw version 
/*
 * pANS stdio -- ftello
 */
#include "iolib.h"
long long ftello(FILE *f){
	long long seekp=seek(f->fd, 0L, 1);
	if(seekp<0) return -1;		/* enter error state? */
	switch(f->state){
	default:
		return seekp;
	case RD:
		return seekp-(f->wp-f->rp);
	case WR:
		return (f->flags&LINEBUF?f->lp:f->wp)-f->buf+seekp;
	}
}