Date: Sun, 25 Aug 1996 23:28:04 -0400 (EDT) From: hoek@freenet.hamilton.on.ca To: KUMAR@BOGPO1.CO.unisys.com Cc: "questions@freebsd.org" <questions@freebsd.org> Subject: Re: Help! Message-ID: <199608260328.XAA29753@james.freenet.hamilton.on.ca>
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In Email, "Kumar, Rao CO" <KUMAR@BOGPO1.CO.unisys.com> wrote: > > Thanks in advance for your time. I saw your mail id on the Internet. So I am > sending you this mail > and would highly appreciate your help. The newsgroup comp.os.msdos.programmer would be a better forum for this question. The mailing-list questions@freebsd.org is intended for answering questions from users of the FreeBSD UNIX-like operating system. MS-DOS has extremely little to do with FreeBSD (fortunately). However, > I have written a TSR (that runs on MS DOS 6.2) that intercepts the interrupt > 1C (timer interrupt). What I am > trying to do in this interrupt handler is some file i/o (using fopen, fread > and fclose of Microsoft C). I'd guess your first problem is that you are using supplied library functions. > At times the system hangs. I thought it was due to some conflict in > simultaneous handling of interrupt 21h by the file i/o calls inside my > routine and the foreground application. So I tried to do a check for the > InDOS > flag before proceeding with my interrupt handling routine, but this flag is > always 1 when my interrupt > routine is invoked (even when there is no front end application). Probably because the InDOS flag is not being set by the front-end application, but by your interrupt handling routine. > 2. Is there any other way to know if MS DOS is executing a 21h interrput ? <shrug> Insert your own 21h interrupt handler to log whatever goes on? -- -- tIM...HOEk The opinions expressed above are mine, and if my employer shares them, that's his hard luck.
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