This is a free implementation of the Cisco ios/asa/catalyst output modifier "begin" released under GNU GPL v.2 or any later version.

http://www.cisco.com/en/US/docs/ios/preface/usingios.html#wp1012384

DEPENDENCIES
This program depends on boost/xpressive header only library. On RedHat(-ish) systems do:

yum install boost-devel

before installation

INSTALLATION
git clone git://github.com/mickenordin/begin.git
cd begin
make
make install