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-rw-r--r--stdio/freopen.c74
1 files changed, 74 insertions, 0 deletions
diff --git a/stdio/freopen.c b/stdio/freopen.c
new file mode 100644
index 0000000000..bedddb1a63
--- /dev/null
+++ b/stdio/freopen.c
@@ -0,0 +1,74 @@
+/* Copyright (C) 1991, 1994, 1995 Free Software Foundation, Inc.
+This file is part of the GNU C Library.
+
+The GNU C Library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Library General Public License as
+published by the Free Software Foundation; either version 2 of the
+License, or (at your option) any later version.
+
+The GNU C Library 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
+Library General Public License for more details.
+
+You should have received a copy of the GNU Library General Public
+License along with the GNU C Library; see the file COPYING.LIB. If
+not, write to the Free Software Foundation, Inc., 675 Mass Ave,
+Cambridge, MA 02139, USA. */
+
+#include <ansidecl.h>
+#include <errno.h>
+#include <stdio.h>
+
+
+/* Defined in fopen.c. */
+extern int __getmode __P ((const char *, __io_mode *));
+
+/* Defined in sysd-stdio.c. */
+extern int __stdio_reopen __P ((const char *filename, __io_mode mode,
+ PTR *cookieptr, __io_close_fn closefn));
+
+/* Replace STREAM, opening it on FILENAME. */
+FILE *
+DEFUN(freopen, (filename, mode, stream),
+ CONST char *filename AND CONST char *mode AND register FILE *stream)
+{
+ __io_mode m;
+ PTR cookie;
+
+ if (!__getmode (mode, &m))
+ {
+ (void) fclose (stream);
+ errno = EINVAL;
+ return NULL;
+ }
+
+ if (stream->__mode.__write)
+ /* Flush the stream. */
+ (void) fflush (stream);
+
+ /* Open the file, attempting to preserve the old cookie value. */
+ cookie = stream->__cookie;
+ if (__stdio_reopen (filename, m, &cookie,
+ stream->__seen ?
+ stream->__io_funcs.__close :
+ __stdio_close))
+ {
+ int save = errno;
+ (void) fclose (stream);
+ errno = save;
+ return NULL;
+ }
+
+ /* Close the stream, first disabling its cookie close function because
+ __stdio_reopen has already dealt with closing the old cookie. */
+ stream->__seen = 1; /* It might have no functions yet. */
+ stream->__io_funcs.__close = NULL;
+ (void) fclose (stream);
+
+ stream->__magic = _IOMAGIC;
+ stream->__cookie = cookie;
+ stream->__mode = m;
+
+ return stream;
+}