ref: a00b6bdbfa72a1688a866edf5f825720c9874ada
dir: /sys/src/libstdio/ftello.c/
/* * 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; } }