I just found a bug in functions/filestat.c which causes
two types of wrong behavior when using the filetype() function:

a) The type of a symlink is only returned correctly, if the link
   points to a regular file. In real life, symlinks can point
   to anything.
b) (even worse). Calling filetype() overwrites the permisssions
   in the global stat cache (IMHO _unwanted_ side-effect).

EXAMPLE:

Situation in real life:
ls -l /tmp
lrwxrwxrwx   1 root     root            4 Aug 13 16:58 dusel -> /usr
-rw-r--r--   1 root     root            0 May  4 00:53 mysqlaccess.log
lrwxrwxrwx   1 root     root           15 Aug 13 16:57 wusel -> mysqlaccess.log

Script:
clearstatcache();
echo filetype("/tmp/dusel") . "<BR>\n";
echo sprintf("%08o", fileperms("/tmp/wusel")) . "<BR>\n";
echo filetype("/tmp/wusel") . "<BR>\n";
echo sprintf("%08o", fileperms("/tmp/wusel")) . "<BR>\n";

Result:
dir
00100644
link
00120777

FIX:

The reason for the above behaviour is in functions/filestat.c, where
a) lstat() is called only for regular files.
b) when calling lstat(), a GLOBAL stbuf is used.

The following patch solves both problems by
a) calling lstat() unconditionally.
b) using a local struct stbuf.

--- functions/filestat.c.orig   Thu Aug 13 17:22:17 1998
+++ functions/filestat.c        Thu Aug 13 17:29:10 1998
@@ -429,6 +429,12 @@
                RETURN_LONG((long)GLOBAL(sb).st_ctime);
                break;
        case 8: /* filetype */
+               {
+                       struct stat lsb;
+                       lstat(GLOBAL(CurrentStatFile),&lsb);
+                       if ((lsb.st_mode&S_IFMT) == S_IFLNK) {
+                               RETURN_STRING("link",1);
+                       }
                switch(GLOBAL(sb).st_mode&S_IFMT) {
                case S_IFIFO:
                        RETURN_STRING("fifo",1);
@@ -443,17 +449,13 @@
                        RETURN_STRING("block",1);
                        break;
                case S_IFREG:
-                       lstat(GLOBAL(CurrentStatFile),&GLOBAL(sb));
-                       if ((GLOBAL(sb).st_mode&S_IFMT) == S_IFLNK) {
-                               RETURN_STRING("link",1);
-                       } else {
                                RETURN_STRING("file",1);
-                       }
                        break;
                default:
                        php3_error(E_WARNING,"Unknown file type (%d)",GLOBAL(sb).st_mode&S_IF
MT);
                        RETURN_STRING("unknown",1);
                        break;
+                       }
                }
                break;
        case 9: /*is writable*/