Re: [bug-diffutils] Incorrect output from cmp

[Jim Meyering]

> I am getting some strange output from cmp on two files. The index is off by 
> one
> for the first and last difference, and both the index and values are wrong for
> the second difference. I tried two versions of cmp (listed below), and I got 
> the
> same output in both cases. My system info is also displayed below.
...

Thanks for the report, but I don't see a problem.
The index is 1-based, not zero-based.
The values are printed in octal, so 16,13 match the 0e,0b
in your hexdump output.

> $ cmp -l file1 file2
>  10   2   4
>  64  16  13
> 200   4   2
>
> $ cmp -l file1 file2 | awk '{printf("%x %x %x\n",$1,$2,$3)}'
> a 2 4
> 40 10 d
> c8 4 2
>
> $ hexdump file1
> 0000000 0c 00 00 00 00 00 00 00 01 02 00 07 0a 00 0b 0a
> 0000010 1f 02 00 00 00 00 00 00 00 00 00 00 00 00 00 00
> 0000020 00 00 00 00 00 00 00 00 00 10 00 00 00 08 00 00
> 0000030 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 0e
> 0000040 00 10 08 08 04 03 20 04 40 00 40 00 00 00 14 00
> 0000050 02 01 00 03 05 08 00 00 00 00 ff ff ff ff 01 03
> 0000060 02 07 ff ff ff ff 01 00 00 00 00 03 02 00 ff ff
> 0000070 ff ff 01 00 00 00 00 03 02 00 ff ff ff ff 01 00
> 0000080 00 00 00 03 02 00 ff ff ff ff 01 00 00 00 00 03
> 0000090 02 00 ff ff ff ff 01 00 00 00 00 03 02 00 ff ff
> 00000a0 ff ff 01 00 00 00 00 03 02 00 00 00 00 00 00 00
> 00000b0 00 00 00 00 00 00 01 00 1e 00 00 00 04 00 00 00
> 00000c0 03 07 00 00 00 00 00 04 00 00 00 00 00 00 00 00
> 00000d0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
> *
> 0000200
>
> $ hexdump file2
> 0000000 0c 00 00 00 00 00 00 00 01 04 00 07 0a 00 0b 0a
> 0000010 1f 02 00 00 00 00 00 00 00 00 00 00 00 00 00 00
> 0000020 00 00 00 00 00 00 00 00 00 10 00 00 00 08 00 00
> 0000030 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 0b
> 0000040 00 10 08 08 04 03 20 04 40 00 40 00 00 00 14 00
> 0000050 02 01 00 03 05 08 00 00 00 00 ff ff ff ff 01 03
> 0000060 02 07 ff ff ff ff 01 00 00 00 00 03 02 00 ff ff
> 0000070 ff ff 01 00 00 00 00 03 02 00 ff ff ff ff 01 00
> 0000080 00 00 00 03 02 00 ff ff ff ff 01 00 00 00 00 03
> 0000090 02 00 ff ff ff ff 01 00 00 00 00 03 02 00 ff ff
> 00000a0 ff ff 01 00 00 00 00 03 02 00 00 00 00 00 00 00
> 00000b0 00 00 00 00 00 00 01 00 1e 00 00 00 04 00 00 00
> 00000c0 03 07 00 00 00 00 00 02 00 00 00 00 00 00 00 00
> 00000d0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
> *
> 0000200
...
> $ /opt/local/libexec/gnubin/cmp --version
> cmp (GNU diffutils) 3.2