<pre>
To compile
$ gcc -lXtst -lX11 Util_KeyPressSimulator.c

To create shared library
$ gcc -lXtst -lX11 -c Util_KeyPressSimulator.c -o Util_KeyPressSimulator.o
$ gcc -lXtst -lX11 -shared -o Util_KeyPressSimulator.so Util_KeyPressSimulator.o
</pre>