# 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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