Build.md

@@ -60,6 +60,9 @@ For core-local measurements the paranoid level of 1 is enough to measure applica
 
 If you want to use the Marker API in Fortran programs, LIKWID offers a native Fortran90 interface. To enable it, set `FORTRAN_INTERFACE`  to `true` in `config.mk`. More information using LIKWID with Fortran look at [[Marker API with Fortran90|TutorialMarkerF90]]. 
 
+# Use system Lua instead of internal Lua
+By setting the variables `LUA_INCLUDE_DIR`, `LUA_LIB_DIR`, `LUA_LIB_NAME` (Lua interpreter has to use the same name, e.g. lua5.1) and `LUA_BIN` (directory of the Lua interpreter) in `config.mk`, the internal Lua library and interpreter are deactivated. The LIKWID library is linked against the provided Lua library and the Shebang of all Lua scripts is changed to the system Lua interpreter. LIKWID's Lua interface was patched to support Lua 5.1, 5.2 and 5.3. It is still recommended to use the internal Lua and only basic tests are done before a release.
+
 # Dependencies
 Although we tried to minimize the external dependencies of LIKWID, some advanced tools or only specific tool options require external packages.
 - [[likwid-perfscope|likwid-perfscope]] uses the Perl script [feedGnuplot](https://github.com/dkogan/feedgnuplot) to forward the real-time data to [gnuplot](http://www.gnuplot.info/). [feedGnuplot](https://github.com/dkogan/feedgnuplot) is included into LIKWID, but [gnuplot](http://www.gnuplot.info/) itself is not.