DOS4GW = DOS 4GB extender for
Watcom. It was a hugely popular
DOS-extender that allowed
32 bit code and large
segments on DOS. Actually, it was an crippled version of the full DOS4G
(high-IRQ's were disabled). Thanks to that,
soundcards with
IRQ's over 7 never worked with
DOOM. Anyways, this piece of
shitty coding was distributed with Watcom C/C++ 10/11.
There's a freeware replacement called PMODE/W that actually works and is a lot smaller.