bitbake: bitbake-user-manual: Added new "Line Joining" section.
Fixes [YOCTO #10444] Added a new section about syntax called "Line Joining". The section describes how you can use the backslash character (\) to joing stuff. (Bitbake rev: a2768ecae7846d72a1bdb7cbbc5e8d242af854f6) Signed-off-by: Scott Rifenbark <srifenbark@gmail.com> Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
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@ -61,6 +61,48 @@
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</para>
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</para>
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</section>
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</section>
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<section id='line-joining'>
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<title>Line Joining</title>
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<para>
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Outside of
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<link linkend='functions'>functions</link>, BitBake joins
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any line ending in a backslash character ("\")
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with the following line before parsing statements.
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The most common use for the "\" character is to split variable
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assignments over multiple lines, as in the following example:
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<literallayout class='monospaced'>
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FOO = "bar \
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baz \
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qaz"
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</literallayout>
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Both the "\" character and the newline character
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that follow it are removed when joining lines.
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Thus, no newline characters end up in the value of
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<filename>FOO</filename>.
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</para>
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<para>
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Consider this additional example where the two
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assignments both assign "barbaz" to
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<filename>FOO</filename>:
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<literallayout class='monospaced'>
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FOO = "barbaz"
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FOO = "bar\
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baz"
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</literallayout>
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<note>
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BitBake does not interpret escape sequences like
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"\n" in variable values.
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For these to have an effect, the value must be passed
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to some utility that interprets escape sequences,
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such as <filename>printf</filename> or
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<filename>echo -n</filename>.
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</note>
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</para>
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</section>
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<section id='variable-expansion'>
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<section id='variable-expansion'>
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<title>Variable Expansion</title>
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<title>Variable Expansion</title>
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