--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,11 @@
+2011-05-13  Eric Blake  <eblake@redhat.com>
+
+	getcwd-lgpl: relax test for FreeBSD
+	* doc/posix-functions/getcwd.texi (getcwd): Document portability
+	issue.
+	* tests/test-getcwd-lgpl.c (main): Relax test.
+	Reported by Matthias Bolte.
+
 2011-05-11  Eric Blake  <eblake@redhat.com>
 
 	test-fflush: silence compiler warning

--- a/doc/posix-functions/getcwd.texi
+++ b/doc/posix-functions/getcwd.texi
@@ -11,8 +11,7 @@
 @itemize
 @item
 On glibc platforms, @code{getcwd (NULL, n)} allocates memory for the result.
-On some other platforms, this call is not allowed.  Conversely, mingw fails
-to honor non-zero @code{n}.
+On some other platforms, this call is not allowed.
 @item
 On some platforms, the prototype for @code{getcwd} uses @code{int}
 instead of @code{size_t} for the size argument:
@@ -30,4 +29,11 @@
 
 Portability problems not fixed by Gnulib:
 @itemize
+@item
+When using @code{getcwd(NULL, nonzero)}, some platforms, such as glibc
+or cygwin, allocate exactly @code{nonzero} bytes and fail with
+@code{ERANGE} if it was not big enough, while other platforms, such as
+FreeBSD or mingw, ignore the size argument and allocate whatever size
+is necessary.  If this call succeeds, an application cannot portably
+access beyond the string length of the result.
 @end itemize

--- a/tests/test-getcwd-lgpl.c
+++ b/tests/test-getcwd-lgpl.c
@@ -65,12 +65,22 @@
     pwd2 = malloc (len + 2);
     for ( ; i <= len; i++)
       {
+        char *tmp;
         errno = 0;
         ASSERT (getcwd (pwd2, i) == NULL);
         ASSERT (errno == ERANGE);
+        /* Allow either glibc or BSD behavior, since POSIX allows both.  */
         errno = 0;
-        ASSERT (getcwd (NULL, i) == NULL);
-        ASSERT (errno == ERANGE);
+        tmp = getcwd (NULL, i);
+        if (tmp)
+          {
+            ASSERT (strcmp (pwd1, tmp) == 0);
+            free (tmp);
+          }
+        else
+          {
+            ASSERT (errno == ERANGE);
+          }
       }
     ASSERT (getcwd (pwd2, len + 1) == pwd2);
     pwd2[len] = '/';
@@ -80,6 +90,11 @@
   ASSERT (strstr (pwd2, "/../") == NULL);
   ASSERT (strstr (pwd2 + 1 + (pwd2[1] == '/'), "//") == NULL);
 
+  /* Validate a POSIX requirement on size.  */
+  errno = 0;
+  ASSERT (getcwd(pwd2, 0) == NULL);
+  ASSERT (errno == EINVAL);
+
   free (pwd1);
   free (pwd2);