From f60d891b2309cdc6f2cc1507a238cec85e4aa9e7 Mon Sep 17 00:00:00 2001
From: Martin Sustrik <sustrik@250bpm.com>
Date: Thu, 6 May 2010 10:33:01 +0200
Subject: [PATCH] Issue 23. zmq_init() crashes on illegal numbers

---
 src/zmq.cpp | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/src/zmq.cpp b/src/zmq.cpp
index ecb3d3de..fb7a7f97 100644
--- a/src/zmq.cpp
+++ b/src/zmq.cpp
@@ -230,7 +230,10 @@ size_t zmq_msg_size (zmq_msg_t *msg_)
 //  Reflect this in the API/ABI.
 void *zmq_init (int /*app_threads_*/, int io_threads_, int /*flags_*/)
 {
-    //  There are no context flags defined at the moment, so flags_ is ignored.
+    if (io_threads_ < 0) {
+        errno = EINVAL;
+        return NULL;
+    }
 
 #if defined ZMQ_HAVE_OPENPGM
     //  Unfortunately, OpenPGM doesn't support refcounted init/shutdown, thus,