What’s the regex syntax used by HaProxy ACL, is that somehow HaProxy specific ore is it using a specific library. I’m asking because each programming language is using their own falvour of regular expressions and I wonder what’s being used by ACL in HaProxy.

Which regex engine is used can been seen in the haproxy -vv output (“haproxy -vv | grep PCRE”). Usually that is PCRE. Since haproxy 1.8 there is also support for PCRE2 and we have a fallback to libc’s RE engine in case haproxy is not linked against PCRE.

Documentation about Regex Syntax

Help!

jurgenhaas January 22, 2018, 5:34pm 3

Thanks a lot @lukastribus

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Documentation about Regex Syntax

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