Updated to fedora-glibc-20050302T1820

19 files changed, 662 insertions, 5 deletions

diff --git a/posix/Makefile b/posix/Makefile
index 3af9e6681d..f08ec9f1f8 100644
--- a/posix/Makefile
+++ b/posix/Makefile
@@ -28,7 +28,7 @@ headers	:= sys/utsname.h sys/times.h sys/wait.h sys/types.h unistd.h	      \
 	   bits/local_lim.h tar.h bits/utsname.h bits/confname.h	      \
 	   bits/waitflags.h bits/waitstatus.h sys/unistd.h sched.h	      \
 	   bits/sched.h re_comp.h wait.h bits/environments.h cpio.h	      \
-	   sys/sysmacros.h spawn.h
+	   sys/sysmacros.h spawn.h bits/unistd.h
 
 distribute := confstr.h TESTS TESTS2C.sed testcases.h \
 	      PTESTS PTESTS2C.sed ptestcases.h \
@@ -83,7 +83,10 @@ tests		:= tstgetopt testfnm runtests runptests	     \
 		   tst-nice tst-nanosleep tst-regex2 \
 		   transbug tst-rxspencer tst-pcre tst-boost \
 		   bug-ga1 tst-vfork1 tst-vfork2 tst-waitid \
-		   tst-getaddrinfo2 bug-glob1 bug-glob2 tst-sysconf
+		   tst-getaddrinfo2 bug-glob1 bug-glob2 tst-sysconf \
+		   tst-execvp1 tst-execvp2 tst-execlp1 tst-execlp2 \
+		   tst-execv1 tst-execv2 tst-execl1 tst-execl2 \
+		   tst-execve1 tst-execve2 tst-execle1 tst-execle2
 xtests		:= bug-ga2
 ifeq (yes,$(build-shared))
 test-srcs	:= globtest
diff --git a/posix/bits/unistd.h b/posix/bits/unistd.h
new file mode 100644
index 0000000000..215063f07d
--- /dev/null
+++ b/posix/bits/unistd.h
@@ -0,0 +1,84 @@
+/* Checking macros for unistd functions.
+   Copyright (C) 2005 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, write to the Free
+   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
+
+#ifndef _UNISTD_H
+# error "Never include <bits/unistd.h> directly; use <unistd.h> instead."
+#endif
+
+extern ssize_t __read_chk (int __fd, void *__buf, size_t __nbytes,
+			   size_t __buflen) __wur;
+#define read(fd, buf, nbytes) \
+  (__bos0 (buf) != (size_t) -1						      \
+   && (!__builtin_constant_p (nbytes) || (nbytes) > __bos0 (buf))	      \
+   ? __read_chk (fd, buf, nbytes, __bos0 (buf))				      \
+   : read (fd, buf, nbytes))
+
+#ifdef __USE_UNIX98
+extern ssize_t __pread_chk (int __fd, void *__buf, size_t __nbytes,
+			    __off_t __offset, size_t __bufsize) __wur;
+extern ssize_t __pread64_chk (int __fd, void *__buf, size_t __nbytes,
+			      __off64_t __offset, size_t __bufsize) __wur;
+# ifndef __USE_FILE_OFFSET64
+#  define pread(fd, buf, nbytes, offset) \
+  (__bos0 (buf) != (size_t) -1						      \
+   && (!__builtin_constant_p (nbytes) || (nbytes) > __bos0 (buf))	      \
+   ? __pread64_chk (fd, buf, nbytes, offset, __bos0 (buf))		      \
+   : pread (fd, buf, offset, nbytes))
+# else
+#  define pread(fd, buf, nbytes, offset) \
+  (__bos0 (buf) != (size_t) -1						      \
+   && (!__builtin_constant_p (nbytes) || (nbytes) > __bos0 (buf))	      \
+   ? __pread_chk (fd, buf, nbytes, offset, __bos0 (buf))		      \
+   : pread (fd, buf, offset, nbytes))
+# endif
+
+# ifdef __USE_LARGEFILE64
+#  define pread64(fd, buf, nbytes, offset) \
+  (__bos0 (buf) != (size_t) -1						      \
+   && (!__builtin_constant_p (nbytes) || (nbytes) > __bos0 (buf))	      \
+   ? __pread64_chk (fd, buf, nbytes, offset, __bos0 (buf))		      \
+   : pread64 (fd, buf, offset, nbytes))
+# endif
+#endif
+
+#if defined __USE_BSD || defined __USE_XOPEN_EXTENDED || defined __USE_XOPEN2K
+extern int __readlink_chk (__const char *__restrict __path,
+			   char *__restrict __buf, size_t __len,
+			   size_t __buflen)
+     __THROW __nonnull ((1, 2)) __wur;
+# define readlink(path, buf, len) \
+  (__bos (buf) != (size_t) -1						      \
+   && (!__builtin_constant_p (len) || (len) > __bos (buf))		      \
+   ? __readlink_chk (path, buf, len, __bos (buf))			      \
+   : readlink (path, buf, len))
+#endif
+
+extern char *__getcwd_chk (char *__buf, size_t __size, size_t __buflen)
+     __THROW __wur;
+#define getcwd(buf, size) \
+  (__bos (buf) != (size_t) -1						      \
+   && (!__builtin_constant_p (size) || (size) > __bos (buf))		      \
+   ? __getcwd_chk (buf, size, buflen) : getcwd (buf, size))
+
+#if defined __USE_BSD || defined __USE_XOPEN_EXTENDED
+extern char *__getwd_chk (char *__buf, size_t buflen)
+     __THROW __nonnull ((1)) __attribute_deprecated__ __wur;
+#define getwd(buf) \
+  (__bos (buf) != (size_t) -1 ? __getwd_chk (buf, buflen) : getwd (buf))
+#endif
diff --git a/posix/execvp.c b/posix/execvp.c
index 9ccfd7fc22..0abfa7007c 100644
--- a/posix/execvp.c
+++ b/posix/execvp.c
@@ -189,7 +189,7 @@ execvp (file, argv)
 	__set_errno (EACCES);
 
       free (script_argv);
-      free (name);
+      free (name - pathlen);
       if (path_malloc)
 	free (path);
     }
diff --git a/posix/regcomp.c b/posix/regcomp.c
index 1a5f7952c3..a7112cffdd 100644
--- a/posix/regcomp.c
+++ b/posix/regcomp.c
@@ -1321,6 +1321,11 @@ lower_subexp (err, preg, node)
   bin_tree_t *op, *cls, *tree1, *tree;
 
   if (preg->no_sub
+      /* We do not optimize empty subexpressions, because otherwise we may
+	 have bad CONCAT nodes with NULL children.  This is obviously not
+	 very common, so we do not lose much.  An example that triggers
+	 this case is the sed "script" /\(\)/x.  */
+      && node->left != NULL
       && (node->token.opr.idx >= 8 * sizeof (dfa->used_bkref_map)
 	  || !(dfa->used_bkref_map & (1 << node->token.opr.idx))))
     return node->left;
diff --git a/posix/regex_internal.h b/posix/regex_internal.h
index f065cf449d..58fa749e90 100644
--- a/posix/regex_internal.h
+++ b/posix/regex_internal.h
@@ -60,7 +60,7 @@
 # ifdef _LIBC
 #  undef gettext
 #  define gettext(msgid) \
-  INTUSE(__dcgettext) (INTUSE(_libc_intl_domainname), msgid, LC_MESSAGES)
+  INTUSE(__dcgettext) (_libc_intl_domainname, msgid, LC_MESSAGES)
 # endif
 #else
 # define gettext(msgid) (msgid)
diff --git a/posix/rxspencer/tests b/posix/rxspencer/tests
index a8b6e4baa8..b84a270cda 100644
--- a/posix/rxspencer/tests
+++ b/posix/rxspencer/tests
@@ -376,6 +376,7 @@ a(b?c)+d	-	accd	accd
 a[bc]d		-	xyzaaabcaababdacd	abd
 a[ab]c		-	aaabc	abc
 abc		s	abc	abc
+()		s	abc	@abc
 a*		&	b	@b
 
 # Let's have some fun -- try to match a C comment.
diff --git a/posix/tst-execl1.c b/posix/tst-execl1.c
new file mode 100644
index 0000000000..1cfa36df12
--- /dev/null
+++ b/posix/tst-execl1.c
@@ -0,0 +1,22 @@
+#include <errno.h>
+#include <stdio.h>
+#include <unistd.h>
+
+static int
+do_test (void)
+{
+  static const char prog[] = "does-not-exist";
+  errno = 0;
+  execl (prog, prog, NULL);
+
+  if (errno != ENOENT)
+    {
+      printf ("errno = %d (%m), expected ENOENT\n", errno);
+      return 1;
+    }
+
+  return 0;
+}
+
+#define TEST_FUNCTION do_test ()
+#include "../test-skeleton.c"
diff --git a/posix/tst-execl2.c b/posix/tst-execl2.c
new file mode 100644
index 0000000000..5b74959ef8
--- /dev/null
+++ b/posix/tst-execl2.c
@@ -0,0 +1,58 @@
+#include <errno.h>
+#include <stdio.h>
+#include <unistd.h>
+#include <sys/stat.h>
+
+
+static void prepare (int argc, char *argv[]);
+static int do_test (void);
+#define PREPARE(argc, argv) prepare (argc, argv)
+#define TEST_FUNCTION do_test ()
+#include "../test-skeleton.c"
+
+
+static char *copy;
+
+static void
+prepare (int argc, char *argv[])
+{
+  char *buf;
+  int off;
+  asprintf (&buf, "cp %s %n%s-copy", argv[0], &off, argv[0]);
+  if (buf == NULL)
+    {
+      puts ("asprintf  failed");
+      exit (1);
+    }
+  if (system (buf) != 0)
+    {
+      puts ("system  failed");
+      exit (1);
+    }
+
+  /* Make it not executable.  */
+  copy = buf + off;
+  if (chmod (copy, 0666) != 0)
+    {
+      puts ("chmod  failed");
+      exit (1);
+    }
+
+  add_temp_file (copy);
+}
+
+
+static int
+do_test (void)
+{
+  errno = 0;
+  execl (copy, copy, NULL);
+
+  if (errno != EACCES)
+    {
+      printf ("errno = %d (%m), expected EACCES\n", errno);
+      return 1;
+    }
+
+  return 0;
+}
diff --git a/posix/tst-execle1.c b/posix/tst-execle1.c
new file mode 100644
index 0000000000..adea0a8d46
--- /dev/null
+++ b/posix/tst-execle1.c
@@ -0,0 +1,22 @@
+#include <errno.h>
+#include <stdio.h>
+#include <unistd.h>
+
+static int
+do_test (void)
+{
+  static const char prog[] = "does-not-exist";
+  errno = 0;
+  execle (prog, prog, NULL, "FOO=BAR", NULL);
+
+  if (errno != ENOENT)
+    {
+      printf ("errno = %d (%m), expected ENOENT\n", errno);
+      return 1;
+    }
+
+  return 0;
+}
+
+#define TEST_FUNCTION do_test ()
+#include "../test-skeleton.c"
diff --git a/posix/tst-execle2.c b/posix/tst-execle2.c
new file mode 100644
index 0000000000..fb9b09b423
--- /dev/null
+++ b/posix/tst-execle2.c
@@ -0,0 +1,58 @@
+#include <errno.h>
+#include <stdio.h>
+#include <unistd.h>
+#include <sys/stat.h>
+
+
+static void prepare (int argc, char *argv[]);
+static int do_test (void);
+#define PREPARE(argc, argv) prepare (argc, argv)
+#define TEST_FUNCTION do_test ()
+#include "../test-skeleton.c"
+
+
+static char *copy;
+
+static void
+prepare (int argc, char *argv[])
+{
+  char *buf;
+  int off;
+  asprintf (&buf, "cp %s %n%s-copy", argv[0], &off, argv[0]);
+  if (buf == NULL)
+    {
+      puts ("asprintf  failed");
+      exit (1);
+    }
+  if (system (buf) != 0)
+    {
+      puts ("system  failed");
+      exit (1);
+    }
+
+  /* Make it not executable.  */
+  copy = buf + off;
+  if (chmod (copy, 0666) != 0)
+    {
+      puts ("chmod  failed");
+      exit (1);
+    }
+
+  add_temp_file (copy);
+}
+
+
+static int
+do_test (void)
+{
+  errno = 0;
+  execle (copy, copy, NULL, "FOO=BAR", NULL);
+
+  if (errno != EACCES)
+    {
+      printf ("errno = %d (%m), expected EACCES\n", errno);
+      return 1;
+    }
+
+  return 0;
+}
diff --git a/posix/tst-execlp1.c b/posix/tst-execlp1.c
new file mode 100644
index 0000000000..1be4dbcb1b
--- /dev/null
+++ b/posix/tst-execlp1.c
@@ -0,0 +1,34 @@
+#include <errno.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+static int
+do_test (void)
+{
+  char *cwd = get_current_dir_name ();
+  if (cwd == NULL)
+    {
+      puts ("get_current_dir_name failed");
+      return 1;
+    }
+
+  /* Make sure we do not find a binary with the name we are going to
+     use.  */
+  setenv ("PATH", cwd, 1);
+
+  static const char prog[] = "does-not-exist";
+  errno = 0;
+  execlp (prog, prog, NULL);
+
+  if (errno != ENOENT)
+    {
+      printf ("errno = %d (%m), expected ENOENT\n", errno);
+      return 1;
+    }
+
+  return 0;
+}
+
+#define TEST_FUNCTION do_test ()
+#include "../test-skeleton.c"
diff --git a/posix/tst-execlp2.c b/posix/tst-execlp2.c
new file mode 100644
index 0000000000..81a723dda4
--- /dev/null
+++ b/posix/tst-execlp2.c
@@ -0,0 +1,82 @@
+#include <errno.h>
+#include <libgen.h>
+#undef basename
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <sys/stat.h>
+
+
+static void prepare (int argc, char *argv[]);
+static int do_test (void);
+#define PREPARE(argc, argv) prepare (argc, argv)
+#define TEST_FUNCTION do_test ()
+#include "../test-skeleton.c"
+
+
+static char *copy;
+
+static void
+prepare (int argc, char *argv[])
+{
+  char *buf;
+  int off;
+  asprintf (&buf, "cp %s %n%s-copy", argv[0], &off, argv[0]);
+  if (buf == NULL)
+    {
+      puts ("asprintf  failed");
+      exit (1);
+    }
+  if (system (buf) != 0)
+    {
+      puts ("system  failed");
+      exit (1);
+    }
+
+  /* Make it not executable.  */
+  copy = buf + off;
+  if (chmod (copy, 0666) != 0)
+    {
+      puts ("chmod  failed");
+      exit (1);
+    }
+
+  add_temp_file (copy);
+}
+
+
+static int
+do_test (void)
+{
+  /* Make sure we do not find a binary with the name we are going to
+     use.  */
+  char *bindir = strdupa (copy);
+  bindir = canonicalize_file_name (dirname (bindir));
+  if (bindir == NULL)
+    {
+      puts ("canonicalize_file_name failed");
+      return 1;
+    }
+  char *path;
+  asprintf (&path, "%s:../libio:../elf", bindir);
+  if (path == NULL)
+    {
+      puts ("asprintf  failed");
+      return 1;
+    }
+
+  setenv ("PATH", path, 1);
+
+  char *prog = basename (copy);
+  errno = 0;
+  execlp (prog, prog, NULL);
+
+  if (errno != EACCES)
+    {
+      printf ("errno = %d (%m), expected EACCES\n", errno);
+      return 1;
+    }
+
+  return 0;
+}
diff --git a/posix/tst-execv1.c b/posix/tst-execv1.c
new file mode 100644
index 0000000000..57ed1add6e
--- /dev/null
+++ b/posix/tst-execv1.c
@@ -0,0 +1,22 @@
+#include <errno.h>
+#include <stdio.h>
+#include <unistd.h>
+
+static int
+do_test (void)
+{
+  char *argv[] = { (char *) "does-not-exist", NULL };
+  errno = 0;
+  execv (argv[0], argv);
+
+  if (errno != ENOENT)
+    {
+      printf ("errno = %d (%m), expected ENOENT\n", errno);
+      return 1;
+    }
+
+  return 0;
+}
+
+#define TEST_FUNCTION do_test ()
+#include "../test-skeleton.c"
diff --git a/posix/tst-execv2.c b/posix/tst-execv2.c
new file mode 100644
index 0000000000..a5168a269c
--- /dev/null
+++ b/posix/tst-execv2.c
@@ -0,0 +1,60 @@
+#include <errno.h>
+#include <stdio.h>
+#include <unistd.h>
+#include <sys/stat.h>
+
+
+static void prepare (int argc, char *argv[]);
+static int do_test (void);
+#define PREPARE(argc, argv) prepare (argc, argv)
+#define TEST_FUNCTION do_test ()
+#include "../test-skeleton.c"
+
+
+static char *copy;
+
+static void
+prepare (int argc, char *argv[])
+{
+  char *buf;
+  int off;
+  asprintf (&buf, "cp %s %n%s-copy", argv[0], &off, argv[0]);
+  if (buf == NULL)
+    {
+      puts ("asprintf  failed");
+      exit (1);
+    }
+  if (system (buf) != 0)
+    {
+      puts ("system  failed");
+      exit (1);
+    }
+
+  /* Make it not executable.  */
+  copy = buf + off;
+  if (chmod (copy, 0666) != 0)
+    {
+      puts ("chmod  failed");
+      exit (1);
+    }
+
+  add_temp_file (copy);
+}
+
+
+static int
+do_test (void)
+{
+  char *argv[] = { copy, NULL };
+
+  errno = 0;
+  execv (copy, argv);
+
+  if (errno != EACCES)
+    {
+      printf ("errno = %d (%m), expected EACCES\n", errno);
+      return 1;
+    }
+
+  return 0;
+}
diff --git a/posix/tst-execve1.c b/posix/tst-execve1.c
new file mode 100644
index 0000000000..356610f635
--- /dev/null
+++ b/posix/tst-execve1.c
@@ -0,0 +1,23 @@
+#include <errno.h>
+#include <stdio.h>
+#include <unistd.h>
+
+static int
+do_test (void)
+{
+  char *argv[] = { (char *) "does-not-exist", NULL };
+  char *envp[] = { (char *) "FOO=BAR", NULL };
+  errno = 0;
+  execve (argv[0], argv, envp);
+
+  if (errno != ENOENT)
+    {
+      printf ("errno = %d (%m), expected ENOENT\n", errno);
+      return 1;
+    }
+
+  return 0;
+}
+
+#define TEST_FUNCTION do_test ()
+#include "../test-skeleton.c"
diff --git a/posix/tst-execve2.c b/posix/tst-execve2.c
new file mode 100644
index 0000000000..1a804e94fd
--- /dev/null
+++ b/posix/tst-execve2.c
@@ -0,0 +1,61 @@
+#include <errno.h>
+#include <stdio.h>
+#include <unistd.h>
+#include <sys/stat.h>
+
+
+static void prepare (int argc, char *argv[]);
+static int do_test (void);
+#define PREPARE(argc, argv) prepare (argc, argv)
+#define TEST_FUNCTION do_test ()
+#include "../test-skeleton.c"
+
+
+static char *copy;
+
+static void
+prepare (int argc, char *argv[])
+{
+  char *buf;
+  int off;
+  asprintf (&buf, "cp %s %n%s-copy", argv[0], &off, argv[0]);
+  if (buf == NULL)
+    {
+      puts ("asprintf  failed");
+      exit (1);
+    }
+  if (system (buf) != 0)
+    {
+      puts ("system  failed");
+      exit (1);
+    }
+
+  /* Make it not executable.  */
+  copy = buf + off;
+  if (chmod (copy, 0666) != 0)
+    {
+      puts ("chmod  failed");
+      exit (1);
+    }
+
+  add_temp_file (copy);
+}
+
+
+static int
+do_test (void)
+{
+  char *argv[] = { copy, NULL };
+  char *envp[] = { (char *) "FOO=BAR", NULL };
+
+  errno = 0;
+  execve (copy, argv, envp);
+
+  if (errno != EACCES)
+    {
+      printf ("errno = %d (%m), expected EACCES\n", errno);
+      return 1;
+    }
+
+  return 0;
+}
diff --git a/posix/tst-execvp1.c b/posix/tst-execvp1.c
new file mode 100644
index 0000000000..ecc673d124
--- /dev/null
+++ b/posix/tst-execvp1.c
@@ -0,0 +1,34 @@
+#include <errno.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+static int
+do_test (void)
+{
+  char *cwd = get_current_dir_name ();
+  if (cwd == NULL)
+    {
+      puts ("get_current_dir_name failed");
+      return 1;
+    }
+
+  /* Make sure we do not find a binary with the name we are going to
+     use.  */
+  setenv ("PATH", cwd, 1);
+
+  char *argv[] = { (char *) "does-not-exist", NULL };
+  errno = 0;
+  execvp (argv[0], argv);
+
+  if (errno != ENOENT)
+    {
+      printf ("errno = %d (%m), expected ENOENT\n", errno);
+      return 1;
+    }
+
+  return 0;
+}
+
+#define TEST_FUNCTION do_test ()
+#include "../test-skeleton.c"
diff --git a/posix/tst-execvp2.c b/posix/tst-execvp2.c
new file mode 100644
index 0000000000..7e0f5d882c
--- /dev/null
+++ b/posix/tst-execvp2.c
@@ -0,0 +1,82 @@
+#include <errno.h>
+#include <libgen.h>
+#undef basename
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <sys/stat.h>
+
+
+static void prepare (int argc, char *argv[]);
+static int do_test (void);
+#define PREPARE(argc, argv) prepare (argc, argv)
+#define TEST_FUNCTION do_test ()
+#include "../test-skeleton.c"
+
+
+static char *copy;
+
+static void
+prepare (int argc, char *argv[])
+{
+  char *buf;
+  int off;
+  asprintf (&buf, "cp %s %n%s-copy", argv[0], &off, argv[0]);
+  if (buf == NULL)
+    {
+      puts ("asprintf  failed");
+      exit (1);
+    }
+  if (system (buf) != 0)
+    {
+      puts ("system  failed");
+      exit (1);
+    }
+
+  /* Make it not executable.  */
+  copy = buf + off;
+  if (chmod (copy, 0666) != 0)
+    {
+      puts ("chmod  failed");
+      exit (1);
+    }
+
+  add_temp_file (copy);
+}
+
+
+static int
+do_test (void)
+{
+  /* Make sure we do not find a binary with the name we are going to
+     use.  */
+  char *bindir = strdupa (copy);
+  bindir = canonicalize_file_name (dirname (bindir));
+  if (bindir == NULL)
+    {
+      puts ("canonicalize_file_name failed");
+      return 1;
+    }
+  char *path;
+  asprintf (&path, "%s:../libio:../elf", bindir);
+  if (path == NULL)
+    {
+      puts ("asprintf  failed");
+      return 1;
+    }
+
+  setenv ("PATH", path, 1);
+
+  char *argv[] = { basename (copy), NULL };
+  errno = 0;
+  execvp (argv[0], argv);
+
+  if (errno != EACCES)
+    {
+      printf ("errno = %d (%m), expected EACCES\n", errno);
+      return 1;
+    }
+
+  return 0;
+}
diff --git a/posix/unistd.h b/posix/unistd.h
index 744c10c50b..d6cd152b46 100644
--- a/posix/unistd.h
+++ b/posix/unistd.h
@@ -734,7 +734,7 @@ extern int ttyslot (void) __THROW;
 extern int link (__const char *__from, __const char *__to)
      __THROW __nonnull ((1, 2)) __wur;
 
-#if defined __USE_BSD || defined __USE_XOPEN_EXTENDED
+#if defined __USE_BSD || defined __USE_XOPEN_EXTENDED || defined __USE_XOPEN2K
 /* Make a symbolic link to FROM named TO.  */
 extern int symlink (__const char *__from, __const char *__to)
      __THROW __nonnull ((1, 2)) __wur;
@@ -1046,6 +1046,12 @@ extern void swab (__const void *__restrict __from, void *__restrict __to,
 extern char *ctermid (char *__s) __THROW __nonnull ((1));
 #endif
 
+
+/* Define some macros helping to catch buffer overflows.  */
+#if __USE_FORTIFY_LEVEL > 0 && !defined __cplusplus
+# include <bits/unistd.h>
+#endif
+
 __END_DECLS
 
 #endif /* unistd.h  */