from John Gilmore to support gcc

[unix-history] / usr / src / usr.bin / pascal / libpc / UNSYNC.c

/* Copyright (c) 1979 Regents of the University of California */

static char sccsid[] = "@(#)UNSYNC.c 1.4 %G%";

#include "h00vars.h"

/*
* push back last char read to prepare for formatted read
*/
UNSYNC(curfile)

       register struct iorec   *curfile;
{
       if (curfile->funit & FWRITE) {
               ERROR("%s: Attempt to read, but open for writing\n",
                       curfile->pfname);
               return;
       }
       if (curfile->funit & EOFF) {
               ERROR("%s: Tried to read past end of file\n", curfile->pfname);
               return;
       }
       if ((curfile->funit & SYNC) == 0) {
               ungetc(*curfile->fileptr, curfile->fbuf);
       }
       curfile->funit &= ~EOLN;
       curfile->funit |= SYNC;
}