bash: Managing Processes

$ ps

Show running processes for user. Some options include:

• -e (See every process)
• -f (Full format)
• -F (Extra full output)
• -u (Another long format)
• -H (Hierarchical format)
• --forest (Output ASCII tree)

Show user's processes running in background mode:

$ jobs -l

Use the command htop for real-time process info. (Which is similar to the Task Manager if you're coming from Windows.) btop is a another useful process manager.

Move background process x to foreground:

$ fg x

Start running process x in background:

$ bg x

$ kill pid

Sends TERM signal to specified PID (Process ID). Some options include:

• -s signal (Specify alternate signal to send)
• -l (Show list of available signals)
• $ killall name* (Kill all processes starting with a name of name)

• 1 - HUP (Hangs up)
• 2 - INT (Interrupts)
• 3 - QUIT (Stops running)
• 9 - KILL (Unconditionally terminates)
• 11 - SEGV (Produces segment violation)
• 15 - TERM (Terminates if possible)
• 17 or 19 - STOP (Stops unconditionally, but doesn't terminate)
• 18 or 20 - TSTP (Stops or pauses, but continues to run in background)
• 19 or 18 - CONT (Resumes execution after STOP or TSTP)

• O (Running on processor)
• S (Sleeping)
• R (Running)
• Z (Zombie, process terminated but parent not available)
• T (Traced or stopped)
• D (Interruptible sleep)

• UID (User responsible for launching process)
• PPID (Process ID of the parent process)
• PID (Process ID of the process)
• PRI (Priority of the process, with higher numbers = lower priority)
• NI (Nice value, used for determining priorities)
• S (State/Status of the process)
• C (Processor utilization over lifetime of the process)
• STIME (System time when process was started)
• TTY (Terminal device from which the process was launched)
• TIME (Cumulative CPU time required to run the process)
• CMD (The name of the program that was started)
• F (System flags assigned to the process)
• ADDR (Memory address of the process)
• SZ (Approximate amount of swap space required if process were swapped out)
• WCHAN (Address of the kernel function where process is sleeping)

• USER (User responsible for launching process)
• PID (Process ID of the process)
• PRI (Priority of the process, higher numbers = lower priority)
• NI (Nice value, used for determining priorities)
• S (State/Status of the process)
• VIRT (Amount of virtual memory used by the process)
• RES (Amount of physical memory used by the process)
• SHR (Amount of memory the process is sharing with other processes)
• %CPU (Share of CPU time that the process is using)
• %MEM (Share of available physical memory the process is using)
• TIME+ (Total CPU time the process has used since starting)
• COMMAND (The command line name of the process)