1 files changed, 64 insertions, 0 deletions
diff --git a/sysdeps/posix/mkstemp.c b/sysdeps/posix/mkstemp.c
new file mode 100644
index 0000000000..9f4f68d72d
--- /dev/null
+++ b/sysdeps/posix/mkstemp.c
@@ -0,0 +1,64 @@
+/* Copyright (C) 1991, 1992 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 <string.h>
+#include <errno.h>
+#include <stdio.h>
+#include <fcntl.h>
+#include <unistd.h>
+
+/* Generate a unique temporary file name from TEMPLATE.
+   The last six characters of TEMPLATE must be "XXXXXX";
+   they are replaced with a string that makes the filename unique.
+   Returns a file descriptor open on the file for reading and writing.  */
+int
+DEFUN(mkstemp, (template), char *template)
+{
+  static CONST char letters[]
+    = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789";
+  size_t len;
+  size_t i;
+
+  len = strlen (template);
+  if (len < 6 || strcmp (&template[len - 6], "XXXXXX"))
+    {
+      errno = EINVAL;
+      return -1;
+    }
+
+  if (sprintf (&template[len - 5], "%.5u",
+	       (unsigned int) getpid () % 100000) != 5)
+    /* Inconceivable lossage.  */
+    return -1;
+
+  for (i = 0; i < sizeof (letters); ++i)
+    {
+      int fd;
+
+      template[len - 6] = letters[i];
+
+      fd = open (template, O_RDWR|O_CREAT|O_EXCL, 0666);
+      if (fd >= 0)
+	return fd;
+    }
+
+  /* We return the null string if we can't find a unique file name.  */
+  template[0] = '\0';
+  return -1;
+}