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MSWindows 95: Trying to trace a DPMI program with lDebugX crashes the OS #75
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It is possible that |
My DPMI test program was in error, it frees and zeroes the environment segment at However, when I try to trace the I tested a similar program on an MSWindows 98 SE running on a physical 686 machine and it works just fine after the modification to dpmimini.com. (I didn't test the exact same program on both machines yet.) |
Running https://www.pcjs.org/software/pcx86/sys/windows/win95/4.00.950/
We get an error as shown below, when a simple test program tries to enter DPMI protected mode. It reads:
Screenshot showing the error:
The dpmimini program is included in the disk image https://pushbx.org/ecm/test/20230813/bcdebugx.img which is unlocked on the server for use as a remote disk for PCjs. The source of the program is in https://hg.pushbx.org/ecm/dpmitest/file/845e876b561e/dpmimini.asm
If I run my debugger,
lcdebugx.com dpmimini.com
then on the first trace step (T
command) it informs me that "DPMI entry cannot be hooked!" which is expected on MSWindows 4. However, tracing into the DPMI entrypoint (call far [bp + 00]
instruction at offset 0143h) I get an address of FCB8:2F97 with the instruction bytes 63, 38 that disassemble asarpl [bx + si], di
. If I try to trace this, the machine crashes in the same way as for running only dpmimini. The error message is exactly the same.The text was updated successfully, but these errors were encountered: