directory name when the ms-dos path spec is a root directory of a device.
* registry.cc (reg_key::build_reg): Set 'key_is_invalid' flag rather than using
an INVALID_HANDLE_KEY.
(reg_key::get_int): Test for key validity before performing registry
operations.
(reg_key::set_int): Ditto.
(reg_key::get_string): Ditto.
(reg_key::set_string): Ditto.
(reg_key::kill): Ditto.
(reg_key::~reg_key): Ditto.
interruptible.
(call_handler): Avoid suspending a thread if it owns a mutex. Only set
signal_arrived if the thread was actually interrupted.
(events_init): Initialize module information needed by interruptible().
(sigdelayed): Don't call sig_dispatch_pending since it could screw up
* init.cc (dll_entry): Record module handle of main for use by interruptible().
(proc_subproc): Reorganize handling of terminated child so that the bulk of the
processing comes from the signal thread.
(wait_sig): Force processing of waiting threads if SIGCHLD is not processed.
* sync.cc (muto::release): Set tid == 0 after lock is released or signal
processor will be confused.
