Re: pwd fails to traverse unreadable directory

[Jim Meyering]

Thank you for reporting that!
I've just checked in the patch below.
I'll add tests to coreutils some time next week.

This bug affects only systems with openat support (glibc-2.4 and
newer and Solaris 10).

2007-02-03  Jim Meyering  <address@hidden>

        Make pwd and readlink work also when run with an unreadable parent dir
        on systems with openat support.
        * lib/getcwd.c (__getcwd) [HAVE_PARTLY_WORKING_GETCWD]: Use the system
        provided getcwd function, even when we have openat support.
        Reported by Dmitry V. Levin in <http://bugzilla.redhat.com/227168>.

Index: lib/getcwd.c
===================================================================
RCS file: /sources/gnulib/gnulib/lib/getcwd.c,v
retrieving revision 1.17
diff -u -p -r1.17 getcwd.c
--- lib/getcwd.c        26 Jan 2007 22:16:55 -0000      1.17
+++ lib/getcwd.c        3 Feb 2007 00:07:43 -0000
@@ -140,13 +140,18 @@ __getcwd (char *buf, size_t size)
   size_t allocated = size;
   size_t used;

-#if HAVE_PARTLY_WORKING_GETCWD && !defined AT_FDCWD
+#if HAVE_PARTLY_WORKING_GETCWD
   /* The system getcwd works, except it sometimes fails when it
      shouldn't, setting errno to ERANGE, ENAMETOOLONG, or ENOENT.  If
      AT_FDCWD is not defined, the algorithm below is O(N**2) and this
      is much slower than the system getcwd (at least on GNU/Linux).
      So trust the system getcwd's results unless they look
-     suspicious.  */
+     suspicious.
+
+     Use the system getcwd even if we have openat support, since the
+     system getcwd works even when a parent is unreadable, while the
+     openat-based approach does not.  */
+
 # undef getcwd
   dir = getcwd (buf, size);
   if (dir || (errno != ERANGE && !is_ENAMETOOLONG (errno) && errno != ENOENT))