Apache Reference: http_core
http_core - Apache Base Functionality
Since Apache 1.0, src/main/http_core.c
The Apache Group (1994)
http_core is the base module of Apache, in which all core functionality is implemented. Although this module also uses the Apache Module API, it is a special one: it has a nonstandard file name (http_core instead of the expected mod_core), it works with special non-API links, and links between the Apache internals and this module are mandatory. In other words, although you can usually strip down Apache at buildtime by removing unnecessary modules, the http_core module can never be removed.
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