# info > KILL

---
type: CommandReference
command: kill
mode: info
section: 
source: info
---

## Quick Reference

- `kill PID` — send SIGTERM to process
- `kill -9 PID` — send SIGKILL to process
- `kill -TERM PID` — send SIGTERM by name
- `kill -l` — list signal names
- `kill -t` — list signal table with descriptions
- `kill -s SIGNAL PID` — send signal by name
- `kill -0 PID` — test if process exists
- `kill -15 -1` — send SIGTERM to all processes (negative PID)

## Name

`kill` — send a signal to processes, or list information about signals

## Synopsis

kill [-s SIGNAL | --signal SIGNAL | -SIGNAL] PID...
kill [-l | --list | -t | --table] [SIGNAL]...
PID semantics:
- Positive PID → send to that process
- PID = 0 → send to all processes in the current process group
- PID = -1 → send to all processes the user can signal (system-dependent exceptions)
- PID < -1 → send to all processes in the process group equal to `|PID|`

If a negative PID is the first argument, precede it with `--` (though `kill -SIGNAL -PID` works without `--` as a common extension).

## Options

- `-s SIGNAL`, `--signal SIGNAL` — specify the signal to send (name or number)
- `-SIGNAL` — shorthand for signal (must be uppercase, e.g., `-TERM`, `-9`)
- `-l`, `--list` — list signal names; if SIGNAL is given, print its number instead
- `-t`, `--table` — print table of signal numbers, names, and descriptions
- `--help` — display help and exit
- `--version` — output version information and exit
- Signal number `0` — test whether a process exists (no signal sent)

Signal names: canonical form or prefixed by `SIG`; case ignored except for the `-SIGNAL` option.

## Examples

Test if a process exists:
shell
kill -0 PID
Send SIGTERM (default) to a process:
shell
kill PID
Send SIGKILL:
shell
kill -9 PID
Send SIGTERM to all processes (negative PID):
shell
kill -15 -1
kill -TERM -1
kill -s TERM -- -1
kill -- -1
List all signal names:
shell
kill -l
List signal table with descriptions:
shell
kill -t
Avoid shell built-in interference:
shell
env kill ...
## See Also

- [kill(1) man page](https://man7.org/linux/man-pages/man1/kill.1.html) — standard Linux man page
- [GNU coreutils manual](https://www.gnu.org/software/coreutils/manual/coreutils.html#kill-invocation) — detailed documentation
- `signal(7)` — overview of signals