bug#8391: chmod setuid & setguid bits

[Ondrej Vasik]

On Fri, 2012-02-24 at 11:22 -0800, Paul Eggert wrote:
> On 02/24/2012 11:05 AM, Ondrej Vasik wrote:
> > requester was fine with double zero 5+ octal digit
> > approach.
> 
> I expect the requester would also be fine with a leading-'@'
> approach.  All the requester wanted was *some* solution.
> 
> 
> > 00755 is still octal digit (and easy to get with printf %5.5o
> > from shorter octal digit mode, and probably easy to use further in
> > scripts without modifications)
> 
> Sorry, I don't follow.  If I have a decimal mode 'mode' in a script,
> then this:
> 
>   chmod @$(printf %o $mode) DIR
> 
> is easier and simpler than this:
> 
>   chmod $(printf %5.5o $mode) DIR
> 
> The "5.5o" is tricky: Why *two* "5"s?
> and who can remember which "5" is really needed, and why,
> right off the bat? and remember why "5", and not "4" or "6"?
> 
> The "@" is simple.

Yes, but `chmod @755 DIR' approach will not let you to write a script
which will work without modification on RHEL-4,RHEL-5 and RHEL-6
machine... which is not the case with fully octal mode. That's what I'm
trying to say with "you still have octal digit". This %5.5o was more
about "easy" change to their script which will allow them to use one
script on everything again...
This kind of approach (one script for more systems) is very common in
enterprise area - and without possibility of doing that, requester will
not be fine with the solution.

Greetings,
         Ondrej