ref: 31f66da43347e73de92995b7e50f1df1c0e8131f
dir: /sys/src/ape/lib/ap/stdio/ftello.c/
/* * pANS stdio -- ftello */ #include "iolib.h" off_t ftello(FILE *f){ off_t seekp=lseek(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; } }