Linux — kill Command

As a DevOps engineer or system administrator, managing system processes is an integral part of daily tasks. Whether it’s monitoring, debugging, or scaling applications, understanding how to manage processes is key. One of the essential commands that every DevOps engineer should be familiar with is the kill command.

What is kill Command?

At its core, the kill command in UNIX-like operating systems is used to send signals to processes. While the name "kill" might suggest its primary purpose is to terminate processes, it's essential to understand that "kill" is more about sending signals, and the termination (SIGTERM) is just one of the many signals it can send.

Here are some basic examples of how to use the kill command:

• Send the default TERM signal:

$ kill [pid]

• Send a specific signal: You can specify a signal to send using its name or number.

$ kill -SIGNAME [pid]

• Send a signal to multiple processes:

$ kill -SIGNAME [pid1] [pid2] [pid3] ...

• List available signals:

$ kill -l
 1) SIGHUP  2) SIGINT  3) SIGQUIT  4) SIGILL  5) SIGTRAP
 6) SIGABRT  7) SIGBUS  8) SIGFPE  9) SIGKILL 10) SIGUSR1
11) SIGSEGV 12) SIGUSR2 13) SIGPIPE 14) SIGALRM 15)…