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POPassing a Bash Array Element to an Awk Regex Expression
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copied!<p>I've found several questions on how to pass variables from <code>bash</code> into <code>awk</code>, most notably the <code>-v</code> command, but I can't quite seem to get them to do what I want.</p> <p>Outside the script, the command I'm running is</p> <pre><code>awk '$2 ~ /^\/var$/ { print $1 }' /etc/fstab </code></pre> <p>Which searches <code>/etc/fstab</code> for JUST the <code>/var</code> partition, and should either print out the physical mount point, or if there isn't one, nothing at all.</p> <p>Now inside the script I have an array that contains numerous partitions, and what I want to do is iterate through that array to search fstab for each physical mount point. The problem comes in at the fact that the elements in the array have a <code>/</code> in them.</p> <p>So what I want to do (In horrifically incorrect awk) is:</p> <pre><code>PARTITIONS=(/usr /home /var tmp); for ((n=0; n<${#PARTITION[@]}; n++)); do cat /etc/fstab | awk '$2 ~ /^\${PARTITIONS[$n]}$/ { print $1 }'; done </code></pre> <p>But I know that that's not correct. The closest I have right now is:</p> <pre><code>PARTITIONS=(/usr /home /var tmp); for ((n=0; n<${#PARTITION[@]}; n++)); do cat /etc/fstab | awk -v partition="${PARTITIONS[$n]}" '$2 ~ /^\/var$/ { print $1," ",partition }'; done </code></pre> <p>Which at LEAST gets the partition variable into awk, but doesn't help me at all with matching it.</p> <p>So basically, I need to feed the array in, and get the physical partitions back out. Eventually the results will be assigned to another array, but once I get the output I can go from there.</p> <p>I also understand awk can remove the need for the cat at the beginning, but I don't know enough about awk to do that yet. :)</p> <p>Thanks for any help.</p> <p><strong>EDIT</strong></p> <pre><code>cat /etc/fstab | awk -v partition="${PARTITIONS[$n]}" '$2 ~ partition { print $1 }' </code></pre> <p>Approximates what I needed enough to be useful. I was focusing far too much on including the regex apparently. If anyone else could clean this up, it would be much appreciated :)</p>

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