|-p||List currently installed traps|
|-l||List signal names and corresponding numbers|
trap utility is a special shell built-in. It's defined in POSIX, but bash adds some useful extensions as well.
Examples that are POSIX-compatible start with
#!/bin/sh, and examples that start with
#!/bin/bash use a bash extension.
The signals can either be a signal number, a signal name (without the SIG prefix), or the special keyword
Those guaranteed by POSIX are:
|0||EXIT||Always run on shell exit, regardless of exit code|
|2||SIGINT||This is what |
|15||SIGTERM||This is what |