Fix is_symlink() to use S_ISLNK() macro

svn path=/trunk/boinc/; revision=15044

checkin_notes

@@ -3197,3 +3197,11 @@ David  April 13 2008
         client_types.C,h
     lib/
         filesys.C
+
+Charlie April 14 2008
+    - Fix is_symlink() to use S_ISLNK() macro instead of incorrect 
+        (sbuf.st_mode & S_IFLNK), which made it return true for regular files   
+        and caused boinc_resolve_filename() to work incorrectly.
+
+    lib/
+        filesys.C

lib/filesys.C

@@ -92,7 +92,7 @@ int is_dir(const char* path) {
 int is_symlink(const char* path) {
     struct stat sbuf;
     int retval = lstat(path, &sbuf);
-    return (!retval && (sbuf.st_mode & S_IFLNK));
+    return (!retval && S_ISLNK(sbuf.st_mode));
 }
 #endif