[comp.sys.ibm.pc] DOS flags question

kkm@oravax.UUCP (Kambhampati Krishnamurty) (06/17/89)

  I would like to use DOS functions, like writing onto a
diskette, disk etc from a memory resident program. This
resident program would be required to run some diskette/disk
functions when asynchronous external events occur ( from
either an RS-232 communications port or the timer tick
interrupt (int 1ch)). The PC would normally be working on some
user program. When the particular interrupt occurs a disk save
or read would be required. 
 I've heard some things about a flag being set by DOS when DOS
'idles' and that DOS functions (int 21h) could be used by
resident user programs when such a flag is suitably set.

  I would appreciate information either on the net or by
e-mail.

  Thanks in anticipation.

K.Krishnamurty
e-mail : kkm%oravax.uucp@cu-arpa.cs.cornell.edu

ps: if this is not the appropriate newsgroup, then suitable 
directions are sought