bug#10043: md5sum improvment suggestion

[Pádraig Brady]

tags 10043 notabug

On 11/14/2011 08:56 AM, Castet JR wrote:
> md5sum improvment suggestion
> 
> Let assume this:
> 
>   find /lib -type f -name '*dll' |head -n5 >a0.a
> 
>   cat a0.a
> 
> /lib/aspell-0.60/context-filter.dll
> /lib/aspell-0.60/email-filter.dll
> /lib/aspell-0.60/nroff-filter.dll
> /lib/aspell-0.60/sgml-filter.dll
> /lib/aspell-0.60/tex-filter.dll
> 
> 
> md5sum checks file integrity based on the md5 crc, of an single file.
>   md5sum /lib/aspell-0.60/tex-filter.dll
>   0

That's not what happens with coreutils md5sum.
Can you give the output of md5sum --version.
I'm closing the bug for the moment.

> md5sum checks file integrity based on the md5 crc, of an list of files .
>   md5sum -c a0.md5
>   0
> 
> 
> 
> md5sum apparently does not make an a0.md5 signature file from a list of files:
>   find /lib -type f -name '*dll' |head -n5 |while read f; do md5sum $f; done 
> >>a0.md
> 
>   -nasty-  :-(

BTW the above would start an md5sum process for each file,
as well as using shell loops which are slow.
The preferred idiom for this is:

find /lib -type f -name '*dll' | xargs md5sum >a0.md5

cheers,
Pádraig.