Re: Testing for a value not sent to a shell script

I was trying to compare $1 to something. An example from a DOS .BAT file is if
'$1' == ''. Without the quotes around $1, if the parameter was missing, then
the BAT file would enter with an error. Adding quotes supplies something where
a missing parameter would only be NULL.


Thanks Pete.

John McKee



Quoting Pete Hall <pete@xxxxxxxxxxxxxx>:

John McKee wrote:

How do I test for the absence of of a parameter in a shell script?

#!/bin/bash
if [ $1 ] ; then
echo 'Yes!'
else
echo 'No!'
fi

--
Pete Hall
pete@xxxxxxxxxxxxxx
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