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Index > DOS > inital SS:SP value in MZ

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vid
Verbosity in development


Joined: 05 Sep 2003
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vid
what is SS:SP value, when no stack is reserved in header (no "stack 100h")?
Post 27 Feb 2006, 11:09
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Tomasz Grysztar



Joined: 16 Jun 2003
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Tomasz Grysztar
From section 2.4.1:
Quote:
"stack" directive sets up the stack for MZ executable. It can be followed by numerical expression specifying the size of stack to be created automatically or by the far address of initial stack frame when you want to set up the stack manually. When no stack is defined, the stack of default size 4096 bytes will be created.
Post 27 Feb 2006, 13:38
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vid
Verbosity in development


Joined: 05 Sep 2003
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Location: Slovakia
vid
oh... and what happens at "stack 0"? is ss:sp just pointer to some invalid area?
Post 28 Feb 2006, 00:36
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Filter



Joined: 08 Oct 2006
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vid wrote:
oh... and what happens at "stack 0"? is ss:sp just pointer to some invalid area?


Don't EXE files require a stack of some sort? Maybe "stack 0" provides enough for it.
Post 26 Oct 2006, 01:15
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Goplat



Joined: 15 Sep 2006
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Goplat
fasm does not allow "stack 0", but if you put a 0 in the SP field of the header the stack pointer does indeed start at 0. Of course, it would wrap around when you used it, and if not enough extra memory was allocated for a 64kB stack you would be overwriting some stuff in memory.
Post 26 Oct 2006, 01:42
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