source: vendor/bash/3.1/lib/sh/zcatfd.c

/* Copyright (C) 2002 Free Software Foundation, Inc.

   This file is part of GNU Bash, the Bourne Again SHell.

   Bash is free software; you can redistribute it and/or modify it under
   the terms of the GNU General Public License as published by the Free
   Software Foundation; either version 2, or (at your option) any later
   version.

   Bash is distributed in the hope that it will be useful, but WITHOUT ANY
   WARRANTY; without even the implied warranty of MERCHANTABILITY or
   FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
   for more details.
   
   You should have received a copy of the GNU General Public License along
   with Bash; see the file COPYING.  If not, write to the Free Software
   Foundation, 59 Temple Place, Suite 330, Boston, MA 02111 USA. */

#include <config.h>

#include <sys/types.h>

#if defined (HAVE_UNISTD_H)
#  include <unistd.h>
#endif

#include <errno.h>

#include <stdc.h>

#if !defined (errno)
extern int errno;
#endif

extern ssize_t zread __P((int, char *, size_t));
extern int zwrite __P((int, char *, ssize_t));

/* Dump contents of file descriptor FD to OFD.  FN is the filename for
   error messages (not used right now). */
int
zcatfd (fd, ofd, fn)
     int fd, ofd;
     char *fn;
{
  ssize_t nr;
  int rval;
  char lbuf[128];

  rval = 0;
  while (1)
    {
      nr = zread (fd, lbuf, sizeof (lbuf));
      if (nr == 0)
        break;
      else if (nr < 0)
        {
          rval = -1;
          break;
        }
      else if (zwrite (ofd, lbuf, nr) < 0)
        {
          rval = -1;
          break;
        }
    }

  return rval;
}