skip date lines that are NOT followed by to|from|connect 
#!/usr/bin/perl
use strict;
use warnings;

my $datestr = "";
while (<DATA>) {
    if (/^.{15}$/) {
        $datestr = $_;
        next;
    }
    if (/^(.?connect\sto.*|to=.*|host.*)$/) {
        print $datestr;
    }
    print;
    $datestr = "";
}

__DATA__
to=<colossus1821@juno.com>, relay=mx.dca.untd.com[64.136.44.37]:25,
delay=177323, delays=177322/0.02/1.8/0, dsn=4.0.0, status=deferred (ho
+st
mx.dca.untd.com[64.136.44.37] refused to talk to me: 550 Access
denied...0b30748490a5c4c48900e4e9912059c0e18d1d24dd45d1896d5150b1f1755
+1f975b124c9b1b12499b11974d1d44
+099f4d135f440c46d305d...)
Mar 21 18:58:08
Mar 21 18:58:08
Mar 21 18:58:08
to=<scottw@webav.com>, relay=none, delay=187566,
delays=187536/0.05/30/0, dsn=4.4.1, status=deferred (connect to
webav.com[74.117.116.83]:25: Operation timed out)
Mar 21 18:58:08
to=<stevew@webav.com>, relay=none, delay=187566,
delays=187535/0.02/30/0, dsn=4.4.1, status=deferred (connect to
webav.com[74.117.116.83]:25: Operation timed out)
Mar 21 18:58:08
Mar 21 18:58:08
to=<ssams@phoenixformations.com>, relay=none, delay=187576,
delays=187546/0.02/30/0, dsn=4.4.1, status=deferred (connect to
mail.phoenixformations.com[69.61.147.50]:25: Operation timed out)

[download]

Output: 

to=<colossus1821@juno.com>, relay=mx.dca.untd.com[64.136.44.37]:25,
delay=177323, delays=177322/0.02/1.8/0, dsn=4.0.0, status=deferred (ho
+st
mx.dca.untd.com[64.136.44.37] refused to talk to me: 550 Access
denied...0b30748490a5c4c48900e4e9912059c0e18d1d24dd45d1896d5150b1f1755
+1f975b124c9b1b12499b11974d1d44
+099f4d135f440c46d305d...)
Mar 21 18:58:08
to=<scottw@webav.com>, relay=none, delay=187566,
delays=187536/0.05/30/0, dsn=4.4.1, status=deferred (connect to
webav.com[74.117.116.83]:25: Operation timed out)
Mar 21 18:58:08
to=<stevew@webav.com>, relay=none, delay=187566,
delays=187535/0.02/30/0, dsn=4.4.1, status=deferred (connect to
webav.com[74.117.116.83]:25: Operation timed out)
Mar 21 18:58:08
to=<ssams@phoenixformations.com>, relay=none, delay=187576,
delays=187546/0.02/30/0, dsn=4.4.1, status=deferred (connect to
mail.phoenixformations.com[69.61.147.50]:25: Operation timed out)

[download]

In reply to Re: a regexp? by almut
in thread a regexp? by Anonymous Monk

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