Bash: Check for Empty Variable

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Friday, October 23. 2015

Bash: Check for Empty Variable

When working with command line substitutions, one way to check for presence (or lack thereof) of a command line variable: 


if [ "x$1" == "x" ];then
...
fi

If it matches, then there was no command line variable, as in 'x matches x'.

Posted by
Raymond P. Burkholder
in Bash at 12:00 | Comments (0)
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