Re: find -ok ... and reading from stdin

[Russell Shaw]

James Youngman wrote:
> The "-ok command ... {} \;" action of find asks the user if they want
> to run the command, but it otherwise almost exactly like -exec.  When
> the command is run, should its standard input be attached to the same
> file as find's standard input (e.g. the input file or pipe from 'yes'
> for example) or should it just have its input pointed at /dev/null?
>
> Advantages of leaving it as-is
>         - ability to launch an interactive program with -ok.
>
> Advantages of redictecting stdin from /dev/null
> 	- the executed program can't steal input that the user might have 
>   	  expected to be read by the "-ok" action.
>
> See also http://savannah.gnu.org/bugs/?func=detailitem&item_id=13650
>
> Preferences?  Comments?
>
> Regards,
> James.

I haven't used the -ok feature, so this is only my guess of what should happen.

If find is fed with a pipe for stdin, questions asked by -ok should open a new
file descriptor for the controlling tty. If the process group is in a session
that has no controlling tty, then find should block or exit on a TTIN/TTOU 
signal.

It would save scripts being accidently run by batch jobs that would normally
ask questions about doing large deletions. If the user intended that, they
should edit out the -ok command. The other way is to have an extra option
that tells find to assume yes or no for -ok when run without access to a
controlling tty. Maybe -nok for assume "no" and -yok to assume "yes".

My 2c.