www.delorie.com/archives/browse.cgi   search  
Mail Archives: djgpp/1995/05/31/12:17:03

Date: Wed, 31 May 1995 10:28:26 -0400
To: eliz AT is DOT elta DOT co DOT il (Eli Zaretskii), djgpp AT sun DOT soe DOT clarkson DOT edu
From: gantose AT lerc DOT nasa DOT gov (Dave Gantose)
Subject: Re: Manually calling iret functions

Previously from me:
>> I realize that the p-mode handler was installed with
>> _go32_dpmi_chain_protected_mode_interrupt_vector() and so the old p-mode
>> handler will be called every time, but there isn't any old p-mode timer
>> interrupt handler, is there?

Reply from Eli Zaretskii:
>Oh, yes, there is.  Otherwise, the system clock would stop ticking while
>DJGPP program is running, which it doesn't.

Guess I figured that the timer interrupt was normally unhandled in p-mode,
and so was passed down to the real-mode handler. If there really is a p-mode
timer handler, then chaining to it EVERY interrupt (because of having used
_go32_dpmi_chain_protected_mode_interrupt_vector()) would cause the system
time-of-day to gain time if the interrupts were being generated, say, 1000
times per second, no?


=============================================================================
Dave Gantose
ADF, Inc.
2001 Aerospace Pkwy.           phone: (216)977-1376
Brook Park, OH  44142          email: Gantose AT lerc DOT nasa DOT gov

- Raw text -


  webmaster     delorie software   privacy  
  Copyright © 2019   by DJ Delorie     Updated Jul 2019