binary file compare...

[Grant Edwards]

On 2009-04-15, Martin <martin at marcher.name> wrote:
> Hi,
>
> On Mon, Apr 13, 2009 at 10:03 PM, Grant Edwards <invalid at invalid> wrote:
>> On 2009-04-13, SpreadTooThin <bjobrien62 at gmail.com> wrote:
>>
>>> I want to compare two binary files and see if they are the same.
>>> I see the filecmp.cmp function but I don't get a warm fuzzy feeling
>>> that it is doing a byte by byte comparison of two files to see if they
>>> are they same.
>>
>> Perhaps I'm being dim, but how else are you going to decide if
>> two files are the same unless you compare the bytes in the
>> files?
>
> I'd say checksums, just about every download relies on checksums to
> verify you do have indeed the same file.

That's slower than a byte-by-byte compare.

>> You could hash them and compare the hashes, but that's a lot
>> more work than just comparing the two byte streams.
>
> hashing is not exactly much mork in it's simplest form it's 2
> lines per file.

I meant a lot more CPU time/cycles.

-- 
Grant Edwards                   grante             Yow! Was my SOY LOAF left
                                  at               out in th'RAIN?  It tastes
                               visi.com            REAL GOOD!!