Split and join. The preferred way.

[Ed Tanous]

The current disposition on boost is documented here:

https://github.com/openbmc/docs/blob/master/cpp-style-and-conventions.md#boost

In short, so long as we're not compromising the project longevity by
increasing the binary sizes, and using well known, tested libraries,
boost functions are perfectly acceptable to use.  There are several
daemons that use a number of string operations from boost today, so
there are several examples that you could follow.  boost::asio is used
in the new webserver implementation, and there are asio extensions for
sdbusplus.

One thing that's recommended is to at a minimum set
BOOST_SYSTEM_NO_DEPRECATED in your compiler flags, to ensure you're not
linking against a static library for boost::system.

-Ed