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Hi Klod,
This is subtle! "section .bss" is a macro, which expands to "[section .bss]" - and sets the "__SECT__" macro to .bss. The "struc" macro depends on "__SECT__" to get back from the "absolute" section to whatever section we were in. Supposed to be ".bss", but because "[section...]" didn't set "__SECT__", we switch back to ".text", where "__SECT__" was initialized. It *does* tell you...
2010-01-07 05:11:42 UTC in The Netwide Assembler
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If your code ran under XP, but doesn't run under Vista, that ought to give you a clue! MS has "improved" their OS by removing 16-bit support. They've been threatening for years to do it - apparently they have. (I thought it was only 64-bit Vista that dropped dos support - you running 64-bit Vista?)
An emulator called "dosbox" may help.
Best,
Frank.
2010-01-05 17:28:07 UTC in The Netwide Assembler
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What you've got there appears to be Masm code (possibly Tasm). Perhaps Jwasm would assemble it. Or, it wouldn't be hard to translate to something Nasm would assemble.
But it won't run in Vista - this is for real mode dos! (that is, no "dosbox" or emm386.sys loaded - those are VM86 mode).
If you can boot a system that will run it, I'll see if I can dig up some Nasm code that will do the...
2010-01-05 17:08:49 UTC in The Netwide Assembler
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Which version of Nasm did assemble "DOSSEG", ".code", etc., Jim?
Best,
Frank.
2010-01-03 12:19:02 UTC in The Netwide Assembler
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Hi Denis,
I prefer to work from the command line, so I don't have any experience with IDEs. Jeff's AsmIde seems "okay" to me, but I haven't used it much. There was an "ide-nasm" posted here some time ago - requires "GAMBAS", which I've never gotten installed, So I've never tried it. I can dig that up, if you want to have a shot at it.
In a supreme irony, I am chief maintainer of a...
2009-12-26 23:41:35 UTC in The Netwide Assembler
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Linux speaks English??? :)
Hi Denis,
Jeff Owens has put together a package of tools for Linux assembly:
http://linuxasmtools.net/
His "AsmRef" is the best (asm oriented) list of system calls I've found. It is part of the full "AsmTools" package - first thing on the download page - or, you can download just AsmRef separately. Thanks, Jeff!
If you have any questions ("if" is a...
2009-12-23 17:53:48 UTC in The Netwide Assembler
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Okay... Wow, there's a lot of this I don't know how to do in Gas syntax! What you want to do is zero a register for your "result". Then for each character in "217", make sure it's a valid decimal digit (if it's linefeed - 0xA - you're done... maybe quit on any invalid digit), multiply the "result so far" by ten, subtract '0' or 48 or 0x30 from the character to make it a number, add the number to...
2009-12-23 01:30:06 UTC in The Netwide Assembler
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Hi Pizearke,
Sorry for the delay. What you show is Gas code, of course, not Nasm. Maybe we can help you anyway... but I'm not sure what you want to do. You've read up to 500 bytes from stdin. %eax will hold the number of bytes actually read - including the linefeed. Is that what you want to return? You could just "movl %eax, %ebx" - you can see it with "echo $?" - but only %bl is valid, so if...
2009-12-23 00:37:10 UTC in The Netwide Assembler
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Well, Jeff Duntemann has just released the latest edition of "Assembly Language Step by Step"!
http://www.duntemann.com
Or there's Dr. Paul Carter's tutorial:
http://www.drpaulcarter.com/pcasm
And Nasm has a nice manual you can find at:
http://www.nasm.us
There may be more...
Best,
Frank.
2009-11-07 11:31:32 UTC in The Netwide Assembler
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I am highly inexpert on gdb. I consider it "unfriendly".
A quick test on your code seems to be "not stopping" on a breakpoint set at _start. If I put a label after the "nop" and set a breakpoint there (and another "nop" after it), instead of on "_start", it does seem to stop(?).
I'd put an "exit" at the end of this, even if it's intended to only be run in a "sandbox" (although Jeff...
2009-11-06 20:03:26 UTC in The Netwide Assembler
