ls: make readlink error to not disrupt output (try ls -l /proc/self/fd).

libbb: make xmalloc_readlink_or_warn warning more specific.

function                                             old     new   delta
xmalloc_readlink_or_warn                              33      61     +28
showfiles                                           1495    1460     -35
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 1/1 up/down: 28/-35)             Total: -7 bytes

1 files changed, 5 insertions, 1 deletions

diff --git a/libbb/xreadlink.c b/libbb/xreadlink.c
index 6bff4beae..8d232f16b 100644
--- a/libbb/xreadlink.c
+++ b/libbb/xreadlink.c
@@ -91,7 +91,11 @@ char* FAST_FUNC xmalloc_readlink_or_warn(const char *path)
         char *buf = xmalloc_readlink(path);
         if (!buf) {
                 /* EINVAL => "file: Invalid argument" => puzzled user */
-                bb_error_msg("%s: cannot read link (not a symlink?)", path);
+                const char *errmsg = "not a symlink";
+                int err = errno;
+                if (err != EINVAL)
+                        errmsg = strerror(err);
+                bb_error_msg("%s: cannot read link: %s", path, errmsg);
         }
         return buf;
 }