Modify exit() to throw an object and catch it.

* Changed exit from throwing an text string to throwing
  an Error-derived object encapsulating the exit status.
  Then catch it in 'callMain' and return the status.

  Enable this functionality by setting CATCH_EXIT_CODE in settings.js

1 files changed, 16 insertions, 0 deletions

diff --git a/src/library.js b/src/library.js
index 113c955c..1f63e6d0 100644
--- a/src/library.js
+++ b/src/library.js
@@ -1752,9 +1752,25 @@ LibraryManager.library = {
   _exit: function(status) {
     // void _exit(int status);
     // http://pubs.opengroup.org/onlinepubs/000095399/functions/exit.html
+
+#if CATCH_EXIT_CODE
+    function ExitStatus() {
+      this.name = "ExitStatus";
+      this.message = "Program terminated with exit(" + status + ")";
+      this.status = status;
+    };
+    ExitStatus.prototype = new Error();
+    ExitStatus.prototype.constructor = ExitStatus;
+#endif
+
     __shutdownRuntime__();
     ABORT = true;
+
+#if CATCH_EXIT_CODE
+    throw new ExitStatus();
+#else 
     throw 'exit(' + status + ') called, at ' + new Error().stack;
+#endif
   },
   fork__deps: ['__setErrNo', '$ERRNO_CODES'],
   fork: function() {