44 lines
924 B
Plaintext
44 lines
924 B
Plaintext
# TRAPS
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Traps allow a script to execute code on various signals. In [pxltrm](https://github.com/dylanaraps/pxltrm) (*a pixel art editor written in bash*) traps are used to redraw the user interface on window resize. Another use case is cleaning up temporary files on script exit.
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Traps should be added near the start of scripts so any early errors are also caught.
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**NOTE:** For a full list of signals, see `trap -l`.
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## Do something on script exit
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```shell
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# Clear screen on script exit.
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trap 'printf \\e[2J\\e[H\\e[m' EXIT
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```
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## Ignore terminal interrupt (CTRL+C, SIGINT)
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```shell
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trap '' INT
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```
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## React to window resize
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```shell
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# Call a function on window resize.
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trap 'code_here' SIGWINCH
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```
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## Do something before every command
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```shell
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trap 'code_here' DEBUG
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```
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## Do something when a shell function or a sourced file finishes executing
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```shell
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trap 'code_here' RETURN
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```
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<!-- CHAPTER END -->
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