As the title says. Chdir is not omnipresent, so a header is needed... at least for my MSVC:
#ifdef _MSC_VER
#include <direct.h>
#endif
...perhaps the file could use a boilerplate, too :)
I get an error regarding chdir in network_cmd_ingame.cc with mingw, so this has more to do with platform than with compiler.
should be fixed now.
It compiles for me at least.
Here it's fixed, too.