NASM - The Netwide Assembler

NASM Forum => Programming with NASM => Topic started by: JnZn558 on October 22, 2013, 09:50:35 AM

Title: File Signature
Post by: JnZn558 on October 22, 2013, 09:50:35 AM

Hello,

i am studying the source code of alink. have read that alink is written as a companion to nasm. unfortunately alink has no forum, hence I post my question here. Sorry for my bad english. OK, Back to my Question.

in the source code, alink try to read the obj or lib file and identify them by using the magic number of the file. I got figure out some of COFF magic number, please correct me, if it is wrong.

• 0x4c => that is the object file magic number full number are I386MAGIC 0x14c
• 0x4d => that is the dll or exe magic number full number are MZ 0x5a4d
• 0x4e => ?

only 0x4e ( 0x14e ) i cannot find anything about this magic number. Does someone know about it? THX 4 help

Title: Re: File Signature
Post by: encryptor256 on October 22, 2013, 12:10:12 PM

Hi!

Quote

i cannot find anything about this magic number

Maybe, you, don't even have to search for it, because it doesn't want's to be found! :D
Maybe, it is some magic number of some rare, old file format.

I think you don't have to worry about that, just keep going on.


P.S.

That web page is very old, Page last updated 10th July 2000.

Title: Re: File Signature
Post by: Frank Kotler on October 22, 2013, 01:29:42 PM

Well... I'm not very familiar with the Alink source... but I've got it. I guess I see where you're finding that. This is a total WAG! The numbers in question are ascii codes for 'L', 'M', 'N'. Maybe coincidence, or maybe "LE", "MZ", and "NE". If so... http://wiki.osdev.org/NE might help. Apologies if I'm totally on the wrong track.

Best,
Frank

Title: Re: File Signature
Post by: JnZn558 on November 01, 2013, 12:41:12 PM

thx for nice answer @frank, I think that's the point.