* scd/scdaemon.h (scd_command_handler): Fix the return type.
* scd/command.c (scd_command_handler): Not return a value.
* scd/scdaemon.c (pipe_server): Make it auto variable in main.
(main): Use auto PIPE_SERVER variable.
(start_connection_thread): When it's a pipe connection and it
finishes, let the service shutdown.