The official Microsoft tutorial links to the repo with sqlsrv versions that are for php 7.0 and up. I've read about the "mssql" with freetds as an alternative, but, from what I understand, its a deprecated method of connecting to MS SQL servers and it likely won't let me avoid rewriting a bunch of code that's referencing sqlsrv functions.
I'm currently restricted to php 5.6 because one of the large libraries that is being used on the website does not support php 7.0. There is a way to update the library to be compatible with php 7.0, but the amount of effort required to do so is currently out of scope for this project.
Any ideas on how to install sqlsrv in this situation? Or is there no way to avoid upgrading to php7 first, or taking MS SQL out of the equation?