What is a process PID?

PID (Process ID) is a unique identifier assigned by the operating system to each running process. It is used for process management and interaction.

The operating system uses PID for:

• Process identification.
• Resource management (memory, CPU).
• Inter-process communication (IPC).
• Tracking process state (running, waiting, finished).

In Python, you can get the current process's PID using the os module:

import os
# Get the current process's PID
pid = os.getpid()
# Print the PID
print(pid)

To get the parent process's PID, use os.getppid():

import os
# Get the parent process's PID
ppid = os.getppid()
# Print the PPID
print(ppid)

PID is an integral part of process management in modern operating systems.