Fixed compilation on *BSD systems

TODO

@@ -6,6 +6,7 @@ VERSION 2.2 TODO (Optimizations and latency)
 
 * Support for syslog(3).
 * Change the implementation of ZCOUNT to use the augmented skiplist in order to be much faster.
+* Add an explicit test for MULTI/EXEC reloaded in the AOF.
 
 VM TODO
 =======

src/redis.h

@@ -16,6 +16,7 @@
 #include <unistd.h>
 #include <errno.h>
 #include <inttypes.h>
+#include <pthread.h>
 
 #include "ae.h"     /* Event driven programming library */
 #include "sds.h"    /* Dynamic safe strings */