aboutsummaryrefslogtreecommitdiff
path: root/REORG.TODO/sysdeps/posix/dup2.c
diff options
context:
space:
mode:
Diffstat (limited to 'REORG.TODO/sysdeps/posix/dup2.c')
-rw-r--r--REORG.TODO/sysdeps/posix/dup2.c56
1 files changed, 56 insertions, 0 deletions
diff --git a/REORG.TODO/sysdeps/posix/dup2.c b/REORG.TODO/sysdeps/posix/dup2.c
new file mode 100644
index 0000000000..3c8e1bcac4
--- /dev/null
+++ b/REORG.TODO/sysdeps/posix/dup2.c
@@ -0,0 +1,56 @@
+/* Copyright (C) 1991-2017 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 Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 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
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, see
+ <http://www.gnu.org/licenses/>. */
+
+#include <errno.h>
+#include <fcntl.h>
+#include <limits.h>
+#include <unistd.h>
+
+/* Duplicate FD to FD2, closing the old FD2 and making FD2 be
+ open the same file as FD is. Return FD2 or -1. */
+int
+__dup2 (int fd, int fd2)
+{
+ int save;
+
+ if (fd2 < 0
+#ifdef OPEN_MAX
+ || fd2 >= OPEN_MAX
+#endif
+)
+ {
+ __set_errno (EBADF);
+ return -1;
+ }
+
+ /* Check if FD is kosher. */
+ if (fcntl (fd, F_GETFL) < 0)
+ return -1;
+
+ if (fd == fd2)
+ return fd2;
+
+ /* This is not atomic. */
+
+ save = errno;
+ (void) close (fd2);
+ __set_errno (save);
+
+ return fcntl (fd, F_DUPFD, fd2);
+}
+libc_hidden_def (__dup2)
+weak_alias (__dup2, dup2)