How to disable output buffering in nginx for PHP application

I didn't want to have to turn off gzip for the whole server or a whole directory, just for a few scripts, in a few specific cases.

All you need is this before anything is echo'ed:

header('Content-Encoding: none;');

Then do the flush as normal:

ob_end_flush();
flush();

Nginx seems to pick up on the encoding having been turned off and doesn't gzip.

Easy solution:

fastcgi_keep_conn on; # < solution

proxy_buffering off;
gzip off;

First php has to correctly flush everything :

@ob_end_flush();
@flush();

Then, I found two working solutions:

1) Via Nginx configuration:

fastcgi_buffering off;

2) Via HTTP header in the php code

header('X-Accel-Buffering: no');