* fhandler.h (fhandler_base::set_open_status): New method. Stores original
open status.
(fhandler_base::get_open_status): New method. Retrieves original open status.
(fhandler_base::reset_to_open_binmode): New method.
* fhandler.cc (fhandler_base::open): Save open status.
(fhandler_base::init): Ditto.
* fhandler_clipboard.cc (fhandler_clipboard::open): Ditto.
* fhandler_console.cc (fhandler_console::open): Ditto.
* fhandler_dsp.cc (fhandler_dsp::open): Ditto.
* fhandler_dev_mem.cc (fhandler_dev_mem::open): Ditto.
* fhandler_dev_random.cc (fhandler_dev_random::open): Ditto.
* fhandler_serial.cc (fhandler_serial::open): Ditto.
* fhandler_tty_slave.cc (fhandler_tty_slave::open): Ditto.
* fhandler_tty_master.cc (fhandler_tty_master::open): Ditto.
* fhandler_dev_zero.cc (fhandler_dev_zero::open): Ditto.
* syscalls.cc (setmode): Rework so that 0 mode value causes reversion to open
state.
* fhandler_tty_slave.cc (fhandler_tty_slave::read): Use correct multiplier when
converting from deciseconds to milliseconds.
* fhandler_dsp.cc: New file. Implements OSS like /dev/dsp.
* include/sys/soundcard.h: New file. User land includes for OSS /dev/dsp.
* fhandler.h: Add new class fhandler_dev_dsp and a FH_OSS_DSP definition.
* dtable.cc (dtable::build_fhandler): Allow creation of the /dev/dsp device.
* path.cc (windows_device_names): Add /dev/dsp into list of device names.
* Makefile.in (DLL_OFILES): Add fhandler_dsp.o.