Display the output of a command from the first line until the first instance of a regular expression.

2010-01-04 0 min read bash Linux
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| perl -n -e 'print "$_" if 1 … /«a class="zem_slink freebase/en/regular_expression" title="Regular expression" rel="wikipedia" href="http://en.wikipedia.org/wiki/Regular_expression">regex>/;# This <a class="zem_slink freebase/en/command_line_interface" title="Command-line interface" rel="wikipedia" href="http://en.wikipedia.org/wiki/Command-line_interface">command line will display the output of , from the first line of output, until the first time it sees a <a class="zem_slink freebase/en/pattern_matching" title="Pattern matching" rel="wikipedia" href="http://en.wikipedia.org/wiki/Pattern_matching">pattern matching .

You could specify the regex pattern /^$/ to look for the first blank line,

or /^foobar/ to look for the first line that starts with the word foobar.

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by David Winterbottom (<a href="http://codeinthehole.com">codeinthehole.com)

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There are couple of other ways you can do so, like using <a class="zem_slink freebase/en/sed" title="Sed" rel="wikipedia" href="http://en.wikipedia.org/wiki/Sed">sed, awk.

|sed –quiet &#8217;/svn_/,$ !p&#8217;<h6 class="zemanta-related-title">Related articles by Zemanta <ul class="zemanta-article-ul"> <li class="zemanta-article-ul-li"><a href="http://www.geekology.co.za/blog/2009/10/using-regular-expressions-part-2-of-4-regex-in-php/">Using Regular Expressions – Part 2 of 4 – Regex in PHP (geekology.co.za) <li class="zemanta-article-ul-li"><a href="http://ianloic.com/2009/06/05/implementing-text-pattern-matching-languages-in-llvm/">Implementing text pattern matching languages in LLVM (ianloic.com) <div class="zemanta-pixie"><a class="zemanta-pixie-a" title="Reblog this post [with Zemanta]" href="http://reblog.zemanta.com/zemified/13a6a746-2174-4fbd-a2fd-5e14f610ce9c/"><img class="zemanta-pixie-img" src="http://blog.amit-agarwal.co.in/wp-content/uploads/2010/08/reblog_b40.png" alt="Reblog this post [with Zemanta]" /><span class="zem-script more-related more-info pretty-attribution paragraph-reblog">

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