reads the BIOS (CMOS RTC) date (at boot). Note that according to
RBIL, DRDOS would even hook int 1a ah=4 to force a correct year.
/* A BIOS with y2k (year 2000) bug will always report year 19nn */
if ((dosregs.c.x >= 1900) && (dosregs.c.x < 1980)) dosregs.c.x += 100;
git-svn-id: https://svn.code.sf.net/p/freedos/svn/kernel/trunk@1359 6ac86273-5f31-0410-b378-82cca8765d1b