UNIX 6th Ed. - /usr/source/iolib/unget.c

   1: # include "ciodec.c"
   2: ungetc (c, fn)
   3: {
   4: struct fileps *fp;
   5: if (nargs() != 2)
   6:    IEHzap("ungetc");
   7: /* push back onto input */
   8: fp = &IEH3fpts[fn];
   9: if (fp->wrflag == 0)
  10:     IEH3mbuf(fn,0);
  11: if (fp->bptr <= fp->buff - 100)
  12:     IEH3err("ungetc/unprintf: buffer full file %d",fn);
  13: *--fp->bptr = c;
  14: fp->nchars++;
  15: }

Defined functions