diff --git a/chapter2/hello-buffer.py b/chapter2/hello-buffer.py
index 0f7a3d1..6d0bd53 100755
--- a/chapter2/hello-buffer.py
+++ b/chapter2/hello-buffer.py
@@ -15,7 +15,7 @@
    struct data_t data = {}; 
    char message[12] = "Hello World";
  
-   data.pid = bpf_get_current_pid_tgid() >> 32;
+   data.pid = bpf_get_current_pid_tgid() & 0xFFFFFFFF;
    data.uid = bpf_get_current_uid_gid() & 0xFFFFFFFF;
    
    bpf_get_current_comm(&data.command, sizeof(data.command));