Readme

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-# CleanC
+# CleanC 0.1
 Improved C interface for Clean
+
+Vanilla Clean requires the programmer to write a separate interface for every C function that is ever going to be called from Clean, directly using the ABC instruction `ccall`. This library removes the need for ABC instructions *entirely*, and allows the programmer to call C functions given their name as a `String`.
+
+Copyright © 2016 Camil Staps. Licensed under MIT, see LICENSE for more details.
+
+### Installation & Usage
+
+To install, simply run:
+
+    make
+
+To use CleanC, you will need to do the following:
+
+ - Add `import CleanC` to your Clean program. 
+ - Link the C object file you want to call code from.
+ - Link `CleanC.o`, `libelf` and `libffi` (may need to install the latter two).
+ - Disable linker optimisation and stripping of the application.
+ - Add the Generics library to the search path.
+
+This gives a clm command line of:
+
+    clm -I "$CLEAN_HOME/lib/Generics" -ns -no-opt-link -l CleanC.o -l myfile.o -l -libelf -l -libffi mymodule
+
+This assumes you have set `$CLEAN_HOME` to the path to your Clean installation.
+
+### Example
+
+See `test.icl`.
+
+### Warning
+This is Bad Code. To be able to call a C function by its name, we need to look through `/proc/self/exe` using libelf.
+
+Since we need `/proc/self/exe`, this is probably linux-specific. Also check the [libffi][libffi] list of supported platforms.
+
+### Acknowledgements
+Code to look up a function pointer by its name was provided by [Falaina on Stack Overflow](http://stackoverflow.com/a/1118808/1544337). Calling a function pointer with extra arguments is possible using [libffi][libffi], as suggested by [FUZxxl](http://stackoverflow.com/a/35088746/1544337).
+
+### Todo
+
+ - Call functions from shared libraries
+ - Improved interface to call Clean from C
+ - Look into Darwin support
+
+### Changelog
+
+ - **0.1** (2016-01-31)
+    - Initial version
+
+[libffi]: https://sourceware.org/libffi/
+