Exact Regex for port Number

theravadamonk has asked for the wisdom of the Perl Monks concerning the following question:

Hi, Monks, I am looking for an EXACT REGEX for a port number?

a few e.g

:42744

:1024

It DON'T want to MATCH my date Jun 19 08:48:50 where : is also present.

I went to https://regex101.com/ and wrote a bit, It WILL catch : of DATE data too

this catches BOTH

:[0-9]+
[download]

Can I have this?

:[0-9]{4,5}
[download]

Your efforts r welcome.

Comment on Exact Regex for port Number Select or Download Code

Replies are listed 'Best First'.
Re: Exact Regex for port Number by Corion (Patriarch) on Jun 19, 2018 at 07:18 UTC
The `ssh` service runs on port 22, so `:22` is both, a valid number of seconds and a valid port number. Your second approach would work, but it would miss port :443 for `https`. Maybe you can be more specific for the situations where a port number is to be expected.	[reply] [d/l] [select]
Re^2: Exact Regex for port Number by theravadamonk (Scribe) on Jun 19, 2018 at 08:15 UTC
Hi,Thank you ALL for your replies. in this case, I am a BIT lucky since I only have higher POTRS from 1024 to 65535 . So I can go with {4,5} So, I go with below code. Thanks once again. Hv a wonderful day. `:[0-9]{4,5}` [download]	[reply] [d/l]
Re^3: Exact Regex for port Number by AnomalousMonk (Archbishop) on Jun 19, 2018 at 10:12 UTC
But `:[0-9]{4,5}` allows port numbers like 1000 and 99999; more range checking is in order. Maybe something like: c:\@Work\Perl\monks>perl -wMstrict -le "for my $pn (qw( :1 :23 :456 :999 :1000 :1023 :1024 :9999 :10000 :65535 :1024x :9999x :10000x :65535x :65536 :99999 :123456 :x :foo : ), '', ' ', @ARGV) { my $pn_ok = $pn =~ m{ : (\d{4,5}) (?! \d) }xms && $1 >= 1024 && $1 <= 65535; print qq{'$pn' }, $pn_ok ? 'in range' : 'BAD'; } " ':1' BAD ':23' BAD ':456' BAD ':999' BAD ':1000' BAD ':1023' BAD ':1024' in range ':9999' in range ':10000' in range ':65535' in range ':1024x' in range ':9999x' in range ':10000x' in range ':65535x' in range ':65536' BAD ':99999' BAD ':123456' BAD ':x' BAD ':foo' BAD ':' BAD '' BAD ' ' BAD [download] Give a man a fish: `<%-{-{-{-<`	[reply] [d/l] [select]
Re: Exact Regex for port Number by hippo (Archbishop) on Jun 19, 2018 at 08:08 UTC
To avoid the chasing of wild geese again, please take a moment to read How to ask better questions using Test::More and sample data.	[reply]
Re: Exact Regex for port Number by QM (Parson) on Jun 19, 2018 at 07:41 UTC
Does the port number occur in a context that can also be matched or not matched? For instance, a look-behind might avoid matching a time, or you might match all dates with priority, then anything left might be a port number. Please can you demonstrate sample strings? (Hopefully you have a full sense of the sample space.) -QM -- Quantum Mechanics: The dreams stuff is made of	[reply]
Re: Exact Regex for port Number by thanos1983 (Parson) on Jun 19, 2018 at 09:48 UTC
Hello theravadamonk, Fellow Monks have tried to tackle your question but from my point of view we are not still able to understand the problem. Can you provide us a sample of string that you want to apply the regex to check the port? For example is it like `<IP>:<PORT>` or is through a URL e.g. `http://www.test.com:80/`, or maybe something else. Help us to help you :) BR / Thanos Seeking for Perl wisdom...on the process of learning...not there...yet!	[reply] [d/l] [select]