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47 lines
1.2 KiB
Plaintext
47 lines
1.2 KiB
Plaintext
\section begin begin - start a new block of code
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\subsection begin-synopsis Synopsis
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<tt>begin; [COMMANDS...;] end</tt>
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\subsection begin-description Description
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The \c begin builtin is used to create a new block of code. The block
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is unconditionally executed. <code>begin; ...; end</tt> is equivalent
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to <tt>if true; ...; end</tt>. The begin command is used to group any
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number of commands into a block. The reason for doing so is usually
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either to introduce a new variable scope, to redirect the input or
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output of a set of commands as a group, or to specify precedence when
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using the conditional commands like \c and.
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The \c begin command does not change the current exit status.
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\subsection begin-example Example
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The following code sets a number of variables inside of a block
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scope. Since the variables are set inside the block and have local
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scope, they will be automatically deleted when the block ends.
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<pre>
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begin
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set -x PIRATE Yarrr
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...
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end
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# This will not output anything, since PIRATE went out of scope at the end of
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# the block and was killed
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echo $PIRATE
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</pre>
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In the following code, all output is redirected to the file out.html.
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<pre>
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begin
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echo $xml_header
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echo $html_header
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if test -e $file
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...
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end
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...
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end > out.html
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</pre>
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