I’ve been using the following code for a while: With Python-2.6 on RHEL6 this works, changing process name to “meow”. With Python-3.7 on RHEL7, however, after going through same code, the process name becomes “m” — just the first letter of the string. What’s going on? Answer The ctypes prctl is probably expecting 8-bit strings, and in Python 3 you’re