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From: Mike Meyer <mwm@mired.org>
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Date: Tue, 23 Oct 2001 20:54:16 -0500
To: Shill <shill@free.fr>
Cc: questions@freebsd.org
Subject: Re: regex(3), re_format(7) and shortest match
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Shill <shill@free.fr> types:
> >> Say I have the string:
> >> "yo <a --- </a> hiphop <a +++ </a> fun"
> >> 
> >> Can anyone tell me how to achieve the shortest match?
> >> 
> >> i.e. the first call to regexec() would return "<a --- </a>"
> >> and the second would return "<a +++ </a>".
> 
> > Try this: (<a[^<]*</a>)
> 
> What if '<' '/' 'a' '>' are all valid characters inside "<a ... </a>"?
> 
> i.e. if I have the string "yo <a %<%/%a%> </a> hiphop" a call to
> regexec() should return "<a %<%/%a%> </a>".
> 
> If I use the (<a[^<]*</a>) regex, it would just return REG_NOMATCH.

Use python re module - or Perl if you must - and then "<a.*?</a>" will
work for your regular expression. The "?" makes the * match the
shortest possible string that matches, which is what you want.

If you have to invoke it from C, the sources to this can be found in
/usr/src/contrib/perl5. Be warned that this is GNU-licensed code, not
BSD-licensed code, so check the license restrictions before
distributing the source or anything built on it.

	<mike
--
Mike Meyer <mwm@mired.org>			http://www.mired.org/home/mwm/
Q: How do you make the gods laugh?		A: Tell them your plans.

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