m/<=\s*(\S+)[^[]+\[([^\]]+)/

Here it is with nicer formatting and a basic explanation:

m/
  <=\s*
  (\S+)    # Capture the email address following <=
  [^[]+\[  # Skip to the first subsequent square bracket.
  ([^\]]+) # Capture until a closing bracket.
/x

[download]

You can tinker with it yourself here.

The email address will be in $1 and the IP will be in $2, following a successful match.

Update: Silly me for trusting the OP's spec. Kenosis mentioned to me that the exim record could, in addition to <= also contain any of ==, **, =>, *>, ->, and possibly some others. So the <= anchor is probably not ideal, but could be improved upon with (?:<=|==|\*\*|=>|\*>|=>) (plus whatever others are legal).


Dave

In reply to Re: String Matching by davido
in thread String Matching by stevbutt

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