67 lines
1.4 KiB
Markdown
67 lines
1.4 KiB
Markdown
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# Bash Functions
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Functions are a great way to reuse code. The structure of a function in bash is quite similar to most languages:
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```bash
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function function_name() {
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your_commands
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}
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```
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You can also omit the `function` keyword at the beginning, which would also work:
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```bash
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function_name() {
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your_commands
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}
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```
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I prefer putting it there for better readability. But it is a matter of personal preference.
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Example of a "Hello World!" function:
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```bash
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#!/bin/bash
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function hello() {
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echo "Hello World Function!"
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}
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hello
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```
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>{notice} One thing to keep in mind is that you should not add the parenthesis when you call the function.
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Passing arguments to a function work in the same way as passing arguments to a script:
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```bash
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#!/bin/bash
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function hello() {
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echo "Hello $1!"
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}
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hello DevDojo
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```
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Functions should have comments mentioning description, global variables, arguments, outputs, and returned values, if applicable
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```bash
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#######################################
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# Description: Hello function
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# Globals:
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# None
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# Arguments:
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# Single input argument
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# Outputs:
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# Value of input argument
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# Returns:
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# 0 if successful, non-zero on error.
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#######################################
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function hello() {
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echo "Hello $1!"
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}
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```
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In the next few chapters we will be using functions a lot!
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