2005-09-20 21:31:55 +08:00
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\section if if - Conditionally execute a command
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\subsection if-synopsis Synopsis
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2006-09-19 22:52:03 +08:00
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<tt>if CONDITION; COMMANDS_TRUE...; [else; COMMANDS_FALSE...;] end</tt>
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2005-09-20 21:31:55 +08:00
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\subsection if-description Description
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2006-09-19 22:52:03 +08:00
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<tt>if</tt> will execute the command CONDITION. If the condition's exit
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status is 0, the commands COMMANDS_TRUE will execute. If it is not 0 and
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<tt>else</tt> is given, COMMANDS_FALSE will be executed. Hint: use
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<a href="#begin"><tt>begin; ...; end</tt></a> for complex conditions.
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2005-09-20 21:31:55 +08:00
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\subsection if-example Example
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<pre>
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if test -f foo.txt
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echo foo.txt exists
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else
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echo foo.txt does not exist
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end
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</pre>
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will print <tt>foo.txt exists</tt> if the file foo.txt
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exists and is a regular file, otherwise it will print
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<tt>foo.txt does not exist</tt>.
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