diff --git a/common/pid.c b/common/pid.c
index 7bd4b8d..c1ec4c2 100644
--- a/common/pid.c
+++ b/common/pid.c
@@ -39,7 +39,7 @@ npid_t PID;
 void init_common_PID (void) {
   if (!PID.pid) {
     int p = getpid ();
-    assert (!(p & 0xffff0000));
+    assert (!(p & 0x80000000));
     PID.pid = p;
   }
   if (!PID.utime) {
diff --git a/common/pid.h b/common/pid.h
index 82f0c4c..b2a1f3b 100644
--- a/common/pid.h
+++ b/common/pid.h
@@ -29,14 +29,14 @@
 struct process_id {
   unsigned ip;
   short port;
-  unsigned short pid;
+  unsigned int pid;
   int utime;
 };
 
 struct process_id_ext {
   unsigned ip;
   short port;
-  unsigned short pid;
+  unsigned int pid;
   int utime;
   int actor_id;
 };