This app can call a function from Unix dynamic library with any number of arguments. Supported types are unsigned / signed int, long, long long, floating point types float, double and C strings char*.
$ clang++ call.cpp -o call -std=c++2a -ldl
-ldl is required to load functions from the dynamic library.
$ <prog> <lib path [optional, default /lib/x86_64-linux-gnu/libc.so.6]> <function name> <args...>
Lib path should start with /, ~/ or ./ to distinguish a library name from a function name.
$ ./call /lib/x86_64-linux-gnu/libm.so.6 cos 6.283185307179586
============ CALLING FUNCTION ============
========== END OF FUNCTION CALL ==========
%rax value = 0
%xmm0 value = 1
$ ./call printf "Hello, it's printf! %lld %lf %lld %lf %lld %lf %lld %lf %lld %lf %lld %lf %lld %lf %lld %lf %lld >%s< and finally %lf" -1 -2.0 3 4.4 5 6.0 7 8.0 9 10.10 11 12.5 13 14.7 15 16.7 17 text 18.8
============ CALLING FUNCTION ============
Hello, it's printf! -1 -2.000000 3 4.400000 5 6.000000 7 8.000000 9 10.100000 11 12.500000 13 14.700000 15 16.700000 17 >text< and finally 18.800000
========== END OF FUNCTION CALL ==========
%rax value = 148
%xmm0 value = 9.53282e-130