These installation instructions are written for a Linux system, but
should work also on other plattforms as Windows is.

Building the plugin requires Geany 0.20 or above (Geany Plugin API v147
or higher).

You need the build environment installed as described at:
http://www.geany.org/manual/reference/howto.html

The following two lines when executed from the shell compile the plugin:

gcc -c geanynumberedbookmarks.c -Wformat=0 -fPIC `pkg-config --cflags geany`
gcc geanynumberedbookmarks.o -o geanynumberedbookmarks.so -shared `pkg-config --libs geany`

The following line moves it into geany's plugin directory

sudo cp geanynumberedbookmarks.so `pkg-config --variable=libdir geany`/geany/

The following lines clean up files used during compilation:

rm geanynumberedbookmarks.o
rm geanynumberedbookmarks.so

