BSD 1 development

[unix-history] / portlib / rew.c

# include       "iodec.h"

/**
**     rewind a file
**/

rew(fn)
int     fn;
{
       register struct fileps  *fp;

       if (fn < 0 || fn >= MAXFILES)
               __error("rew: bad file number %d", fn);
       fp = &__filehdr[fn];
       if (fp->wrflag == 0)
               return;
       switch (fp->wrflag)
       {

         case 3:
               fp->wrflag = 2;
               return;

         case 4:               /* modify */
         case 2:               /* write */
               cflush(fn);

         case 1:               /* read */
               fp->nchars = fp->eoferr = 0;
               seek(fn, 0, 0);
               return;

       }
}