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From: Florian Weimer <fweimer@redhat.com>
To: Anand Akhare <anan.akhare@gmail.com>
Cc: libc-help@sourceware.org
Subject: Re: regexec pattern matching
References: <CACWLfGL2SCtVixe3xzrU=6DyCJGSf3X46Xa5dHeAvx8AOcSDxQ@mail.gmail.com>
Date: Tue, 04 Dec 2018 14:54:00 -0000
In-Reply-To: <CACWLfGL2SCtVixe3xzrU=6DyCJGSf3X46Xa5dHeAvx8AOcSDxQ@mail.gmail.com>	(Anand Akhare's message of "Fri, 2 Nov 2018 14:29:00 +0530")
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* Anand Akhare:

> Hello,
>      regexec matching pattern against buffer throughout complete length
> and skips for those that doesn't match until match is found.
> Is it possible to get match for first character and if match fails, it
> returns fail rather than going forward to next characters.
> In summary, only start of buffer should b considered for match.

I think glibc's non-POSIX matching interfaces (re_search etc.) support
this via the range argument, but I have not tired this.

Thanks,
Florian