Re: [OT] Magic numbers

[Lisi <lisi.reisz@gmail.com>]

On Sunday 06 February 2011 20:35:17 Eduardo M KALINOWSKI wrote:
> On 02/06/2011 06:27 PM, Lisi wrote:
> > I need to find out:
> > a)What the magic number should be for certain types of file and
> > b)Whether a specific file of that type has the correct magic number.
> >
> > Here is my one, so far futile, effort - in addition to googling until I
> > can see magic numbered smoke coming out of my ears. :-(
> >
> > lisi@Tux:~$ cat /usr/share/misc/magic.mgc | grep gzip
> > Binary file (standard input) matches
> > lisi@Tux:~$
> >
> > I realise that this is more specific to UNIX than specific to Debian -
> > but it applies to all the UNIX family, and Debian is part of that family.
> > ;-)
>
> That's a binary file, it won't help you much.
>
> See the corresponding source package, you should find the same
> information in that file in a more readable way.
>
>
> --
> "We shall reach greater and greater platitudes of achievement."
> 		-- Richard J. Daley
>
> Eduardo M KALINOWSKI
> eduardo@kalinowski.com.br

Source code failed because I couldn't find the source code. The gzip that I 
have is a Debian package, and no source code is offered.  BUT

lisi@Tux:~$ cat /usr/share/misc/magic | grep gzip
# still uses gzip for the control.tar (first in the archive).  Only
#>84    string          gz              \b, uses gzip compression
>>14    beshort 0x677a          (gzipped)
>>14    beshort !0x677a         (not gzipped)
>>36    belong&0x4      0x4             gzip
# compress, gzip, pack, compact, huf, squeeze, crunch, freeze, yabba, etc.
# gzip (GNU zip, not to be confused with Info-ZIP or PKWARE zip archiver)
0       string          \037\213        gzip compressed data
!:mime  application/x-gzip
0       string          \037\236        frozen file 1.0 (or gzip 0.5)
# + gzipped tarball files
>512    string          \037\213        \b, gzipped
>>0x2744        lelong  1               gzip compressed
0       string  llvc1   LLVM byte-codes, gzip compression
#>65    string          Gzip            (GNU gzip)
#>69    string          Gzip            (GNU gzip)
>4      string          GZ              (gzip compressed)
>20    belong          2               gzipped
lisi@Tux:~$ 

So all I have to do now is a) interpret it and b) find the, hopefully 
matching, code in a specific file!


Thanks for your help.

Lisi