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PerlFAQ Server 04-19-2011 10:00 AM

FAQ 6.3 How can I pull out lines between two patterns that are themselves on different lines?
 
This is an excerpt from the latest version perlfaq6.pod, which
comes with the standard Perl distribution. These postings aim to
reduce the number of repeated questions as well as allow the community
to review and update the answers. The latest version of the complete
perlfaq is at http://faq.perl.org .

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6.3: How can I pull out lines between two patterns that are themselves on different lines?

You can use Perl's somewhat exotic ".." operator (documented in perlop):

perl -ne 'print if /START/ .. /END/' file1 file2 ...

If you wanted text and not lines, you would use

perl -0777 -ne 'print "$1\n" while /START(.*?)END/gs' file1 file2 ...

But if you want nested occurrences of "START" through "END", you'll run
up against the problem described in the question in this section on
matching balanced text.

Here's another example of using "..":

while (<>) {
$in_header = 1 .. /^$/;
$in_body = /^$/ .. eof;
# now choose between them
} continue {
$. = 0 if eof; # fix $.
}



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