A process is a program in execution. The process that controls the screen is called the foreground process. It can take input from the keyboard and write it to the window.
- programs are compiled into objects (binaries/executables)
- programs in execution are processes
- process images are the memory a process occupies
- 3 kinds of processes
- user
- system
- kernel
Background Processes
More than one process can run in a window by making other processes background processes. This can be done by appending & to a command.
- background processes can't handle i/o
- this can be achieved by writing to a file
ps lists currently running processes.
-lgives lots of information information-fprovides command args
top list the processes using the most CPU resources at a given time
kill <options> <PIDs> sends a kill signal to the listed process, with options allowing more forceful process killing. (up to kill -9)