56 lines
871 B
Plaintext
56 lines
871 B
Plaintext
# OBSOLETE SYNTAX
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## Shebang
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Use `#!/usr/bin/env bash` instead of `#!/bin/bash`.
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- The former searches the user's `PATH` to find the `bash` binary.
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- The latter assumes it is always installed to `/bin/` which can cause issues.
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**NOTE**: There are times when one may have a good reason for using `#!/bin/bash` or another direct path to the binary.
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```shell
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# Right:
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#!/usr/bin/env bash
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# Less right:
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#!/bin/bash
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```
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## Command Substitution
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Use `$()` instead of `` ` ` ``.
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```shell
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# Right.
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var="$(command)"
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# Wrong.
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var=`command`
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# $() can easily be nested whereas `` cannot.
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var="$(command "$(command)")"
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```
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## Function Declaration
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Do not use the `function` keyword, it reduces compatibility with older versions of `bash`.
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```shell
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# Right.
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do_something() {
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# ...
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}
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# Wrong.
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function do_something() {
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# ...
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}
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```
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<!-- CHAPTER END -->
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