[CentOS] less for CentOS6 with POSIX regex?

Mon Jun 8 22:50:16 UTC 2015
Nicolas Thierry-Mieg <Nicolas.Thierry-Mieg at imag.fr>

On 06/09/2015 12:48 AM, Nicolas Thierry-Mieg wrote:
> On 06/09/2015 12:33 AM, tony at softins.co.uk (Tony Mountifield) wrote:
>> In article <ml1jnh$afr$1 at softins.softins.co.uk>,
>> Tony Mountifield <tony at softins.co.uk> wrote:
>>> When I started using CentOS 6 instead of CentOS 5, I discovered that
>>> "less" no longer understood \< and \>, which I had been used to using
>>> since almost forever.
>>> Eventually research revealed that in the Fedora version on which
>>> RHEL 6 was based, "less" had been built with the PCRE regex library
>>> instead of a POSIX one. So instead of \< and \>, I had to use \b.
>>> I found a bugzilla entry about this, which showed that the change had
>>> been reverted in a later Fedora release. So I tested CentOS 7, and found
>>> "less" has been reverted to using POSIX regex, which I'm glad about.
>>> What I want to know is: do any repos have a replacement version of
>>> "less" for CentOS 6 that has been built with POSIX regex, so that
>>> I don't have to keep switching between the two styles when working
>>> on different CentOS versions?
>> Well, after the deafening silence in response, I assumed the answer
>> was "no",
>> so I downloaded the SRPMs of less for both C6 and C7, and did a
>> comparison.
>> I found that it was easy to fix the C6 less to use the correct POSIX
>> regex
>> engine as follows:
>> 1. Copy less-394-search.patch from the C7 SRPM, and add it back into
>>     less.spec as Patch2.
>> 2. Remove the line "BuildRequires: pcre-devel".
>> 3. Remove "--with-regex=pcre" from the %configure line in less.spec.
>> 4. Change the release number. I changed 13 to 13posix, so that the
>> resultant
>>     RPMS have names like less-436-13posix.el6 instead of less-436-13.el6
>> 5. Rebuild RPMs and SRPM using "rpmbuild -ba less.spec".
>> 6. Install using "yum localinstall".
>> The resulting build of less works wonderfully on my C6 boxes,
>> consistently
>> with the versions on C4, C5 and C7.
>> I'm sure there must be other people who would find the corrected RPMs
>> useful,
>> so my questions now are:
>> a) Is there a contributors repo to which it would be appropriate to
>> submit them?
>> b) Is there a better way to number the release for this version?
> it may be better to change the package name to less-posix rather than
> change the release number, and have the new package conflict with less.
> That way once you've installed it, it won't get squashed by a yum update.

you might need to have it provide "less" though, to avoid unmet deps eg 
for man or gzip.