comment on

Changing your regex to

/my background error (\d+):(?!.+my3\.exe)/
[download]

seems to capture what you're after.

Here's a few tests:

$ perl -Mstrict -Mwarnings -E 'while (<>) { if (/my background error ( +\d+):(?!.+my3\.exe)/ ) { say $1 } }' blah blah my background error 1234: blah blah 1234 blah blah my background error 1234: blah blah my3.exe blah blah blah my background error 1234: blah blah my4.exe blah 1234 blah blah my background error 1234: my3.exe blah blah my background error 1234:my3.exe 1234 ^C
[download]

Note the last one with 1234:my3.exe is a match: which seems to follow the pattern you're describing. If you don't want that line either, use .* instead of .+, i.e. change (?!.+my3\.exe) to (?!.*my3\.exe).

UPDATE

I noticed you wanted to capture the text after the error number as well as that number. The solution above doesn't do that. The following regex will:

/my background error (\d+): ((?!.*my3\.exe).+)/
[download]

Retested:

$ perl -Mstrict -Mwarnings -E 'while (<>) { if (/my background error (
+\d+): ((?!.*my3\.exe).+)/ ) { say qq{$1 = \"$2\"} } else { say q{NO M
+ATCH} } }'
blah blah my background error 1234: blah blah
1234 = "blah blah"
blah blah my background error 1234: blah blah my3.exe blah
NO MATCH
blah blah my background error 1234: blah blah my4.exe blah
1234 = "blah blah my4.exe blah"
blah blah my background error 1234: my3.exe
NO MATCH
blah blah my background error 1234:my3.exe
NO MATCH
blah blah my background error 1234: my4.exe
1234 = "my4.exe"
^C
[download]

-- Ken

In reply to Re: negated word issue by kcott
in thread negated word issue by Anonymous Monk

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