(INTERRUPT_INPUT): Undefined.

(INTERRUPT_INPUT): Undefined.
(BROKEN_FIONREAD): Defined to work around a problem in DGUX
whereby emacs will stop on a background write when invoked from a
job control shell for the first time in a session.
(FIRST_PTY_LETTER): Undefined.
(PTY_ITERATION, PTY_NAME_SPRINTF, PTY_TTY_NAME_SPRINTF): Defined
to use all the available PTYs in a COFF environment.
(LINKER): Removed "-nostdlib" from to be compatible with a prior
mod removing "/lib/crt0.o" from the LIBS_SYSTEM define.
(LIBS_SYSTEM): Delete /lib/crt0.o.

(SYSTEM_MALLOC): Turned off.
(NO_TERMIO): Defined.
(BROKEN_FASYNC): Turned off.