plan9front/sys/src/libstdio/fseek.c

24 lines
408 B
C

/*
* pANS stdio -- fseek
*/
#include "iolib.h"
int fseek(FILE *f, long offs, int type){
switch(f->state){
case ERR:
case CLOSED:
return -1;
case WR:
fflush(f);
break;
case RD:
if(type==1 && f->buf!=f->unbuf)
offs-=f->wp-f->rp;
break;
}
if(f->flags&STRING || seek(f->fd, offs, type)==-1) return -1;
if(f->state==RD) f->rp=f->wp=f->buf;
if(f->state!=OPEN)
f->state=RDWR;
return 0;
}