Hello all,

This is a general perl question regarding execution speed.

I wrote a bash script a short while ago (more as a proof-of-concept deal) that I use as part of a custom IDS for my webserver. The script works so well that it is now my main IDS. But, parts of it are slow. Noticably, a loop that performs a single-pass scan on a file containing a list of IPv4 addresses.

This list presently has 1,473 entries and the related bash script function takes about 18 seconds to process on my webserver. My fastest workstation can process it in about 5 seconds. But I suspect perl could do this even quicker.

I'm hoping someone can tell me if this would be the case. The function does very simple integer comparisons between each line looking for matches in the first 3 octets.

I've never programmed in perl but would be prepared to put in the effort to learn it if I knew that 'the end justifies the means'... :)

All opinions are welcome. Thank you for your wisdom.

In reply to perl quicker than bash? by TiffanyButterfly

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