Linux Process Control Blocks

The process control block in Linux (formally named the task_struct) is a data structure maintained by the kernel that contains all of the necessary information to maintain a process on the system. The task_struct is a large struct in the kernel containing many fields. Some example fields are process id (pid), file descriptors, environment variables, the command used to start the process, memory maps, etc. The information specific to a process can be viewed in the /proc/<pid>/ directory. You can learn more in the man pages man procfs. You can find other relevant man pages with apropos proc