Setting headers within process_headers function of module

[Atul Bhouraskar]

Hi,

I am writing an "upstream" module to implement a custom protocol. I have 
managed to get most of it working end to end by following the fastcgi 
module code but am stuck at a problem that should be simple...

I need to set certain HTTP headers within the process_header function as 
the upstream server does not speak HTTP. The two headers that I am most 
interested in at this time are "X-Accel-Redirect" and "Content-Type" 
(populated at different times depending upon content received from 
upstream). The values of both headers are available in the function.

I have tried following the example at 
http://wiki.nginx.org/HeadersManagement (substituting headers_out with 
headers_in) with no luck, the output headers don't seem to change or 
there is a math exception thrown when a nginx internal function is 
performing a hash lookup. Looking at the fastcgi module it seems that 
there might be some hash initialisation that is needed? I haven't been 
able to figure this out.

Any help would be appreciated!

Regards,

Atul