[talk] Comparing Executables

[Sujit K M]

On Tue, Oct 6, 2015 at 9:30 PM, Christos Zoulas <christos at zoulas.com> wrote:
> On Oct 6,  9:26pm, kmsujit at gmail.com (Sujit K M) wrote:
> -- Subject: Re: [talk] Comparing Executables
>
> | Hi Okan,
> |
> | On Tue, Oct 6, 2015 at 9:22 PM, Okan Demirmen <okan at demirmen.com> wrote:
> | > On Tue, Oct 6, 2015 at 11:37 AM, Sujit K M <kmsujit at gmail.com> wrote:
> | >> Hi All,
> | >>
> | >> I was of the opinion that all files including executables can be renamed.
> | >> Hoping this is true, Is there a sleek way in UNIX to find if the two files are
> | >> the same. One thing that comes to my mind is to write a program in C to
> | >> read both the binaries and comparing. The other simpler alternative is to
> | >> use scripting, I don't think we will be stretched to use Python Or Perl.
> | >> But Awk/Sed etc.
> | >>
> | >> Would love to get a feedback.
> | >
> | > fdupes exists, or do it yourself with a similar methodology.
> |
> | fdupes seems to more useful comparing non executable files. What I am
> | looking for
> | is the below scenario.
> |
> | Say you compile an executable with -o flag and -g flag the executable produced
> | is the same application but are different if you compare with say diff.
>
> You mean with -O and without -O and with -g? These will produce
> different code/binaries... But if you compile with "-O -g" and "-O"
> alone you should be able to use objdump --disassemble to compare.

Yeah I mean compile the first binary with -O and other with -g. This
will produce two
different binaries. So where does the law stand on this? If you look
at the BSD/GNU
licenses they just state "source or binary", these are two different
binaries right?