in reply to String Matching

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

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Re^2: String Matching
by stevbutt (Novice) on Aug 14, 2012 at 08:12 UTC

    Thanks Dave,

    The Spec is correct - This is already in a if/ifelse statement where we know if we are dealing with == ** etc So what you have shown me is just perfect,

    many thanks

    Steve

[reply]

      Fantastic! My faith in humanity is restored. ;) ...and I'm glad it worked for you.


      Dave

[reply]

        Sorry Dave, Spoke too soon

        My test box is Linux and it works fine there but the target system is Solaris and only has Perl 5.8.4

        I get errors there as follows

        
Unrecognized escape \S passed through at ./syslog_smtp.pl line 36.
Unrecognized escape \s passed through at ./syslog_smtp.pl line 36.
Unrecognized escape \s passed through at ./syslog_smtp.pl line 36.

        [download]

        Line 36 reads 

        my ( $from, $srvrip ) = $remainder =~ m/<=\s*(\S+)[^[]+\[([^\]]+);

        [download]
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