Cheat Sheet #day66

`kill` Command Cheatsheet

The kill command in Unix-like systems is used to terminate processes by sending signals to them. It allows users to manage and control processes running on the system. Here’s a quick reference guide:

Basic Syntax

kill [OPTIONS] PID...

Common Signals

-1, SIGHUP: Hangup signal. Typically used to instruct a process to reload its configuration.
-2, SIGINT: Interrupt signal. This is typically generated by pressing Ctrl+C and is used to terminate a process gracefully.
-9, SIGKILL: Kill signal. Forces termination of a process. It cannot be caught or ignored by the process.
-15, SIGTERM: Termination signal. This is a general-purpose signal to terminate a process gracefully.

Examples

Terminate a process by PID (default signal is SIGTERM):
```
 kill 1234
```
Send a specific signal to a process (e.g., SIGKILL):
```
 kill -9 1234
```
Send a SIGHUP signal to reload a process (e.g., a daemon):
```
 kill -1 1234
```
Terminate multiple processes by PIDs:
```
 kill 1234 5678 9101
```
Send a SIGINT signal to terminate a process gracefully (e.g., Ctrl+C):
```
 kill -2 1234
```

Additional Options

-l, --list: List available signals. Use with kill -l.
```
  kill -l
```
-s SIGNAL, --signal=SIGNAL: Specify a signal by name or number.
```
  kill -s SIGTERM 1234
```
-p, --pid PID: Specify the process ID.
```
  kill -9 --pid 1234
```

Tips

Graceful Termination: Use SIGTERM (-15) for normal termination as it allows the process to clean up resources.
Forceful Termination: If a process does not respond to SIGTERM, use SIGKILL (-9) to force termination, but this can leave resources in an inconsistent state.

Additional Information

Help option:
```
  kill --help
```
View manual page for kill:
```
  man kill
```

The kill command provides essential functionality for managing processes in Unix-like systems, allowing users to terminate processes gracefully or forcefully depending on the situation. For more detailed information and advanced usage, refer to the man page or use kill --help.

Cheat Sheet #day66 - kill

kill Command Cheatsheet