53 lines
No EOL
1 KiB
Markdown
53 lines
No EOL
1 KiB
Markdown
# Configuration file syntax
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```sh
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# VAR value (the brackets are mandatory)
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${VAR}
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# Set value if not defined (ie set default value)
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VAR ?= "defvalue"
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# Set value at the end of parsing if the value is not defined
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VAR ??= "defvalue"
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# Set VAR to "value" immediately
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VAR := "value"
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# Append "value" to VAR
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# Warning: inserts a space between current value and appended value
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VAR += "value"
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# Same with prepend:
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VAR =+ "value"
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# Same to append/prepend but without space
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VAR .= "value"
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VAR =. "value"
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# Same to append/prepend
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# but without space and deferred at the end of parsing
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VAR_append = "value"
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VAR_prepend = "value"
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# Remove elements (words) in a space-separated value list
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VAR_remove = "value"
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# Like bash functions
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my_function() {
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echo "Hello world"
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}
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# Note that _append suffix also works with functions
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# Function written in python
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python my_function2() {
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print "Hello world"
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}
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```
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<warn data-markdown>
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- `${VAR}` is a Yocto variable.
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- `$VAR` is a shell variable.
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- They are very different !
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</warn> |