The mailing list for listmasters using Sympa

[Miles Fidelman <address@concealed>]

Dick Visser wrote:
> Hi guys
>
> ​ In the
> docs at http://www.sympa.org/manual/authentication#generic_sso_paragraph
> ​
> ​t
> he term 'environment variables' and HTTP headers are
> ​​
> used interchangeably.​
> ​ For instance:​
>
>
> ​
>
>  *
>     |http_header_list|
>     Sympa gets user attributes from environment variables coming from
>     the web server. These variables are then cached in the
>     |user_table| DB table for later use in authorization scenarios (in
>     structure). You can define a coma-separated list of header field
>     names.
>
> ​
> AFAIK, Apache environment variables are something distinctly different 
> than HTTP headers.
> ​Y​
> ou can
> ​ ​
> configure one to be dependent on the other, for instance set HTTP 
> headers based on a the content of some environment variable.
> ​But they're not the same.
>
> Maybe the docs could be updated to clarify this.
Maybe a silly comment, but "duh" - HTTP headers are part of the PDU - 
when Apache processes an incoming HTTP request, it reads the headers and 
has to put them somewhere, which turns out to be in environment 
variables that are then available to CGI scripts (like, say, Sympa)

You need to be looking at the APACHE documentation - maybe starting 
here:  http://httpd.apache.org/docs/trunk/env.html
And the Common Gateway Interface RFC: http://www.ietf.org/rfc/rfc3875 - 
which actually lists the mapping between HTTP headers and env. variables

What is a little confusing is that Apache has two different notions of 
"environment variable" - o/s environment variables, and variables 
maintained by Apache itself.

Miles Fidelman