BBS: Inland Empire Archive
Date: 05-07-92 (09:28)             Number: 162
From: BRENT ASHLEY                 Refer#: NONE
  To: CORIDON HENSHAW               Recvd: NO  
Subj: Redirection                    Conf: (2) Quik_Bas
 CH> What you are missing is someone who wrote a BBS that
 CH> needed redirection to run (!!!)

Ah-Hah!  I figured I missed something....

I found that you can tell if your input and output is redirected through
int21h svc44 subsvc00 (get ioctl device info).  If you ask for STDIN(00) or
STDOUT(01) by setting bx to the handle, you can tell the following from DL:

if bit 7 (MSB) is 1, it's a block device, so must be redirected.

if bit 0 (stdin) (or bit 1 for stdout) isn't set then it's redirected.


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