pure-bash-bible/manuscript/chapter11.txt

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# Traps
Traps allow you to execute code on various signals. In `pxltrm` I'm using traps to redraw the user interface on window resize. Another use case is cleaning up temporary files on script exit.
These `trap` lines should be added near the start of your script so any early errors are also caught.
**NOTE:** For a full list of signals, see `trap -l`.
## Do something on script exit
```shell
# Clear screen on script exit.
trap 'printf \\e[2J\\e[H\\e[m' EXIT
```
## Ignore terminal interrupt (CTRL+C, SIGINT)
```shell
trap '' INT
```
## React to window resize.
```shell
# Call a function on window resize.
trap 'code_here' SIGWINCH
```
## Do something before every command.
```shell
trap 'code_here' DEBUG
```
## Do something when a shell function or a sourced file finishes executing
```shell
trap 'code_here' RETURN
```
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