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is there a certain opcode in a file that i can find to tel me where the file will be loaded? where the base should be

example

org 1000h

No. That's why there's executable file formats, like ELF.

Nope. That's one the points of a relocatable executable file format. Even a simple 2^x byte executable header is perfect for this.

oh, alright, thanks

What I would suggest is passing the base from the kernel to the program in a register such as DX (or EDX in pmode) so the program can then play with that.

What I would suggest is passing the base from the kernel to the program in a register such as DX (or EDX in pmode) so the program can then play with that.

I personally dont recommend that. It is hackish imho and creates an unnecessary dependency between the calling program and OS.

If the program is needing to know where it is located at, there are nicer methods of obtaining that information. ie; like the program calling a API function to obtain it.

Just my 2 cents.

I think it should be possible (just to prove the concept) by locating an absolute jump/call within the first few instructions of the program. This would require some minimal disassembly of the program. By assuming an alignment of the program in the memory, it should be possible to inaccurately determine the load address..