Is ZLIB support in PHP enabled by default or NOT?
This section of the documentation appears to be incorrect. As far as I can tell, the zlib extension has always* been enabled by default.
While it's possible that this extension is not loaded on some systems, this is extremely rare. You do not need to add workarounds for its absence — just state it as a requirement and move on.
*: That is, back to at least PHP 4.0.
Just faced a scenario few days back where I generated the reverse issue as stated by you. The aws linux ami I was working with has a php installation without the zlib configured, due to which I was not getting the zlib package.
I have to re-install the php for the package I wanted i.e. --with-zlib[=DIR] (not recommended, but was a official approach I have to maintain)
So it's not always available by default.Hope that helps.