Added some basic CGI support using kcgi plus a lot of fixes and content updates. (0.41.9)

web/documentation/extensions/kcgi/kcgi.md

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+layout: page
+published: true
+noToc: false
+noComments: false
+noDate: false
+title: Fun - KCGI extension (optional)
+subtitle: Documentation for KCGI (kcgi) extension (optional)
+description: Documentation for KCGI (kcgi) extension (optional)
+permalink: /documentation/extensions/kcgi/
+lang: en
+tags:
+- extension
+- kcgi
+- optional
+---
+
+- CMake option: FUN_WITH_KCGI=ON
+- Purpose: integrate the kcgi (CGI/FastCGI) C library; provide request parsing and response helpers for building CGI apps in Fun.
+- Homepage: [https://kristaps.bsd.lv/kcgi/](https://kristaps.bsd.lv/kcgi/){:class="ext"}
+
+## Build notes:
+
+- Requires system kcgi development headers and libraries (pkg-config name: kcgi).
+- If pkg-config is not available, build falls back to linking against libkcgi and zlib (as configured in cmake/Extensions/KCGI.cmake).
+
+## Provided helper/opcodes:
+
+- Function: kcgi_parse(data: none) -> Map | Nil. Parses the current CGI/FastCGI request via kcgi and returns a Map with keys like method, scheme, host, port, path, suffix, query, and fields (GET/POST map). Returns Nil on failure or when the extension is disabled.
+- Function: kcgi_reply_start(code:int, content_type:string) -> 1/0. Starts the HTTP reply (sets Content-Type and opens the body).
+- Function: kcgi_write(text:string) -> 1/0. Writes a chunk to the response body.
+- Function: kcgi_end() -> 1/0. Finalizes the response and frees request resources.
+- Opcodes: OP_KCGI_PARSE, OP_KCGI_REPLY_START, OP_KCGI_WRITE, OP_KCGI_END (internal mappings for the functions above).
+
+## Quickstart:
+
+- Configure: cmake -S . -B build -DFUN_WITH_KCGI=ON
+- Build: cmake --build build --target fun
+- Run example:
+  - FUN_LIB_DIR="$(pwd)/lib" ./build/fun examples/cgi/hello_kcgi.fun
+
+## Example output:
+
+- Content-Type: text/html; charset=utf-8
+- <h1>Hello, Fun!</h1>
+
+## Notes:
+
+- Running outside a real CGI/FastCGI environment may emit RFC warnings (e.g., missing REMOTE_ADDR); these are benign for local testing.
+- When FUN_WITH_KCGI is OFF, the helpers behave as no-ops (returning Nil/0) to keep scripts portable.