Support symlinking to dart-sdk executables on Linux and Mac.

sdk/bin/dart

Index: sdk/bin/dart
diff --git a/sdk/bin/dart b/sdk/bin/dart
index 22abed8b5e623c3425c39b9798a3754f58c309c8..597892450b67e815c96e354eea65c931394f302d 100755
--- a/sdk/bin/dart
+++ b/sdk/bin/dart
@@ -3,9 +3,20 @@
 # for details. All rights reserved. Use of this source code is governed by a
 # BSD-style license that can be found in the LICENSE file.
 
-# Setting CUR_DIR this way is ugly, but is needed to handle the case where
-# sdk/bin has been symlinked to. On MacOS, readlink doesn't work with this case.
-CUR_DIR="$(cd "${0%/*}" ; pwd -P)"
+function follow_links() {
+  file="$1"
+  while [ -h "$file" ]; do
+    # On Mac OS, readlink -f doesn't work.
+    file="$(readlink "$file")"
+  done
+  echo "$file"
+}
+
+# Unlike $0, $BASH_SOURCE points to the absolute path of this file.	

[ahe, 2013/11/14 15:36:05]

Lines 15-19 have some weird stuff at the end of the line. It show up as red
chevrons in rietveld.

+PROG_NAME="$(follow_links "$BASH_SOURCE")"	
+	
+# Handle the case where dart-sdk/bin has been symlinked to.	
+CUR_DIR="$(cd "${PROG_NAME%/*}" ; pwd -P)"
 
 if [ -z "$DART_CONFIGURATION" ];
 then