emp_server will only dump core if you run with the -d flag.

If you decide not to dump core, then the most recent player commands
should be listed in data/server.log.  Each command will be preceeded
by the country number of the player which issued it.   When the player
is prompted, then [prompt] is printed.

If you decide to dump core, then the most recent player commands will
be in the global array called player_commands which is indexed by
player_commands_index.  The array will contain strings of the form:
  "%3d %3d %s", index, player->cnum, command