Regular expressions

This might be more for the CCSP forum but I feel like I might bet a better response here.

Regular expressions are pretty big for the IPS.

While watching the CBT NUGS for the IPS test the guy states that they are big for BGP also.

With this in mind, how close are cisco's regexs to perl. TO me they look very close.

Just wondering because I get tons of practice with regexs and perl, but not so much with cisco stuff....

Looking for a good way to parctice them, and there are tons of perl web sites that have little quiz questions in regards to regexs. Thinking I could apply this to the cisco stuff...

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Comments

Paul Boz

I practiced Cisco regexes by controling BGP routing updates. I wouldn't say I'm "good" at them but with a reference I can use them okay. I just don't see them enough in my day to day to have them down to memory.

liven

To me they look VERY much like perl Regex....

I use a LOT of perl, typcially daily or weekly... Shoot I just finished a 1000 line script that parses hundreds of files and generates reports of them. And it uses pattern matching for finding the right type of file as it moves through directories.... They it uses perl modules to actually read the files.

However in the past I have applied perl to parse ASA and PIX log files to get failed and successful login attempts and then generate possible brute force reports that get sent to admins.

Just wanted to see if others have any perl knowledge can compare it to Cisco regex....

They seem pretty much the same.

I mean perl takes it another step further. But anyway

mikej412

They are pretty much just regular Regular Expressions from my old UNIX Programming days -- pre-Perl even.

The Doc to know if you can't remember what the Characters do is in the old IOS Terminal Services Documentation:

Regular Expressions

liven

mikej412 wrote:

They are pretty much just regular Regular Expressions from my old UNIX Programming days -- pre-Perl even.

The Doc to know if you can't remember what the Characters do is in the old IOS Terminal Services Documentation:
Regular Expressions

Thanks Feller!!!