diff --git a/ChangeLog b/ChangeLog
index 5a1bc8e600..6fc178b9c3 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+Sun Nov  6 20:13:27 2005  Nobuyoshi Nakada  <nobu@ruby-lang.org>
+
+	* file.c (rb_file_s_readlink): readlink(2) on AIX fails with ERANGE if
+	  buffer size is less than required.  fixed: [ruby-dev:27634]
+
 Sat Nov  5 13:42:50 2005  Nobuyoshi Nakada  <nobu@ruby-lang.org>
 
 	* configure.in, cygwin/GNUmakefile.in (mingw): use def file to alias
diff --git a/file.c b/file.c
index c1a69575f6..38db9d84ba 100644
--- a/file.c
+++ b/file.c
@@ -1982,7 +1982,13 @@ rb_file_s_readlink(VALUE klass, VALUE path)
     rb_secure(2);
     FilePathValue(path);
     buf = xmalloc(size);
-    while ((rv = readlink(StringValueCStr(path), buf, size)) == size) {
+    for (;;) {
+	rv = readlink(RSTRING(path)->ptr, buf, size);
+#ifndef _AIX
+	if (rv != size) break;
+#else
+	if (rv > 0 || errno != ERANGE) break;
+#endif
 	size *= 2;
 	buf = xrealloc(buf, size);
     }