optcode, assembly Code, or binary?

mrpc_cambodia · 01-05-2005, 12:57 AM

hi,

let's say i have a program written in C. i compiled the program.

2 things i want to ask:

1. I want to know the above compiled program will become optCode,assembly code or something else?

2. I heard after we compile a program, it will become binary. so what is this binary? how will it execute? does it need to be translated/compiled a step further for the cpu to understand?

Thanks,

itsme86 · 01-05-2005, 01:02 AM

It gets compiled into an ELF Binary

mrpc_cambodia · 01-05-2005, 01:30 AM

so does the cpu understand this ELF Binary directly? or does ELF binary need to be converted a step further to understand?

Thanks,

itsme86 · 01-05-2005, 01:32 AM

It needs to be processed further, which is done by the kernel. It would be a major security flaw if the kernel allowed users to create code that could be run directly through the CPU. Anyone could crash the computer pretty easily by just faking a binary file with malicious opcodes and running it.

mrpc_cambodia · 01-05-2005, 03:58 AM

Could u tell me the flow/process of this translation?

start from source Code -> ELF binary -> what's next? -> optCode

Thanks,

Marius2 · 01-05-2005, 05:59 AM

The ELF binary consists of opcodes (BTW: operation code, therefore opcode, not optcode).
Additionally the ELF file consists of various data describing the program code, ELF header
(as in http://www.cs.ucdavis.edu/~haungs/paper/node12.html) being the core
element of this data. Of course the cpu has no idea of how to process the header data,
therefore the ELF file is not executable directly, but only via the kernel.

HTH