--- apache-ivy-2.2.0/src/java/org/apache/ivy//util/FileUtil.java	2010-06-28 08:17:10.000000000 +1200
+++ apache-ivy-2.2.0-symlink/src/java/org/apache/ivy//util/FileUtil.java	2011-10-03 15:23:14.617761330 +1300
@@ -27,6 +27,7 @@
 import java.io.OutputStream;
 import java.io.PrintWriter;
 import java.io.StringWriter;
+import java.io.BufferedOutputStream;
 import java.net.URL;
 import java.util.ArrayList;
 import java.util.Collection;
@@ -50,6 +51,22 @@
 
     private static final byte[] EMPTY_BUFFER = new byte[0];
 
+    // currently active symlink helper process
+    private static Process symlinkHelper;
+    private static PrintWriter symlinkHelperStdin;
+    private static BufferedReader symlinkHelperStdout;
+
+    // symlink helper process script, run via sh -c '...' 
+    private static final String symlinkScript =
+        "IFS=; " +
+        "while read -r SRC; do "+ 
+        "  read -r DEST; " +
+        "  read -r FORCE; " +
+        "  error=`ln -s \"$FORCE\" -- \"$SRC\" \"$DEST\" 2>&1`; " +
+        "  if [ $? -ne 0 ]; then echo \"error: $error\" | head -1; else echo \"ok\"; fi; " +
+        "done; " +
+        "echo \"script terminated\"; exit 0";
+    
     public static void symlink(File src, File dest, CopyProgressListener l, boolean overwrite)
             throws IOException {
         try {
@@ -66,30 +83,61 @@
                 dest.getParentFile().mkdirs();
             }
 
-            Runtime runtime = Runtime.getRuntime();
-            Message.verbose("executing 'ln -s -f " + src.getAbsolutePath() + " " + dest.getPath()
-                    + "'");
-            Process process = runtime.exec(new String[] {"ln", "-s", "-f", src.getAbsolutePath(),
-                    dest.getPath()});
-
-            if (process.waitFor() != 0) {
-                InputStream errorStream = process.getErrorStream();
-                InputStreamReader isr = new InputStreamReader(errorStream);
-                BufferedReader br = new BufferedReader(isr);
-
-                StringBuffer error = new StringBuffer();
-                String line;
-                while ((line = br.readLine()) != null) {
-                    error.append(line);
-                    error.append('\n');
+            final PrintWriter stdin;
+            final BufferedReader stdout;
+            synchronized (FileUtil.class) {
+                if (symlinkHelper == null) {
+                    Message.verbose("Starting symlink helper - executing: sh -c '" + symlinkScript + "'");
+
+                    ProcessBuilder builder = new ProcessBuilder(new String[]{"sh", "-c", symlinkScript});
+                    builder.redirectErrorStream(true);
+                    symlinkHelper = builder.start();
+
+                    symlinkHelperStdin = new PrintWriter(new BufferedOutputStream(symlinkHelper.getOutputStream()));
+                    symlinkHelperStdout = new BufferedReader(new InputStreamReader(symlinkHelper.getInputStream()));
+                }
+                
+                stdin = symlinkHelperStdin;
+                stdout = symlinkHelperStdout;                   
+            }
+
+            String result;
+            try {
+                Message.verbose("Requesting symlink of " + src.getAbsolutePath() + " to " + dest.getPath());
+                symlinkHelperStdin.println(src.getAbsolutePath());
+                symlinkHelperStdin.println(dest.getPath());
+                symlinkHelperStdin.println(overwrite ? "-f" : "");
+                symlinkHelperStdin.flush();
+                result = symlinkHelperStdout.readLine();
+            } catch (IOException ioe) {
+                Message.verbose("error writing to symlink helper script: " + ioe);
+                synchronized (FileUtil.class) {
+                    if (symlinkHelper != null)
+                        symlinkHelper.destroy();
+                    symlinkHelper = null;
                 }
 
-                throw new IOException("error symlinking " + src + " to " + dest + ":\n" + error);
+                throw ioe;                
             }
-            
+
+            Message.verbose("Symlink helper responded: " + result);
+
+            if (result == null || (!result.equals("ok") && !result.startsWith("error: "))) {
+                // EOF or unexpected response from script
+                Message.verbose("EOF or unexpected response from symlink helper script");
+                synchronized (FileUtil.class) {
+                    if (symlinkHelper != null)
+                        symlinkHelper.destroy();
+                    symlinkHelper = null;
+                }
+            }
+
+            if (!"ok".equals(result))
+                throw new IOException("while symlinking " + src + " to " + dest + ": " + (result == null ? "helper script EOF" : result));
+
             // check if the creation of the symbolic link was successful
             if (!dest.exists()) {
-                throw new IOException("error symlinking: " + dest + " doesn't exists");
+                throw new IOException("error symlinking: " + dest + " doesn't exist");
             }
             
             // check if the result is a true symbolic link
@@ -103,8 +151,6 @@
             x.printStackTrace(new PrintWriter(buffer));
             Message.debug(buffer.toString());
             copy(src, dest, l, overwrite);
-        } catch (InterruptedException x) {
-            Thread.currentThread().interrupt();
         }
     }