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Unit 3: Apache Server

module AP_MODULE_DECLARE_DATA helloworld2_module = Notes

{
STANDARD20_MODULE_STUFF, /* stuff that needs to be declared in
every 2.0 mod */
NULL, /* create per-directory config structure */

NULL, /* merge per-directory config structures */
NULL, /* create per-server config structure */

NULL, /* merge per-server config structures */
NULL, /* command apr_table_t *

register_hooks /* register hooks */
};
Take this c code name it ‘mod_helloworld2.c’ and save it. Now you can compile it using an apache tool
called apxs. apxs is located in the bin Directory of the Apache 2.0.x build. The command that I used
to compile this mod is ‘apxs -c -i -a mod_helloworld2.c’. This will build our mod and install it.
What good is the code if you don’t see it doing anything? ‘cd’ to the ‘conf’ directory. In this
directory is the file ‘httpd.conf’. Add these lines where it seems appropriate:

<Location /ourmap>
SetHandler helloworld2-handler

</Location>

Give a mod to run, the code for a Hello World.
3.1.4 Module Definition

Every standard Apache mod needs an initial ‘module’ to describe it. By convention this is the
last thing in the module. To define it use:
module AP_MODULE_DECLARE_DATA foobar_module =

Replace ‘foobar’ with the name of the module (the file name minus any extensions).
3.1.5 Standard Module Stuff

There are 14 slots in a standard Apache 2.0 module. We’re fortunate though. The macro
‘STANDARD20 MODULE STUFF’ predefines the first eight of these for us. The macro is defined
in http_config.h if you desire to take a closer look at it. It mostly contains bookkeeping items
such as the major and minor magic numbers for the Apache release.
3.1.6 Config Slots

The next four slots we do not use, so let’s skip them. They have to do with host wide and
directory wide configurations and access.

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