Re: find . -exec TURNIP{} +

[Eric Blake]

[forwarding to bug-findutils]

On 09/03/2010 11:00 AM, Geoff Clare wrote:
> James,
>
> I saw Eric's mail in the bug-findutils archive where he said:
>
> > POSIX says, for -exec ... +:
> >
> > "If a utility_name or argument string contains the two characters "{}",
> > but not just the two characters "{}" , it is implementation-defined
> > whether find replaces those two characters or uses the string without
> > change."
> >
> > Implementation-defined is a bear - it means we have to pick one of those
> > two behaviors, and document it; we are not allowed to pick an alternate
> > third behavior (rejecting with an error message).
>
> I believe Eric is mistaken about this.  POSIX says
>
>      "Only a<plus-sign>  that immediately follows an argument
>      containing the two characters "{}"  shall punctuate the end of the
>      primary expression. Other uses of the<plus-sign>  shall not be
>      treated as special."
>
> So according to POSIX,
>
> find . -exec TURNIP{} +
>
> does not have a terminator on the -exec.  So you are right to give
> an error message, although perhaps you are giving a misleading one.
>
> find plainfile -exec TURNIP{} + \;
>
> is valid and should execute either TURNIP{} or TURNIPplainfile.

Interesting - that indeed implies more work to get this correct.

However, it also means that we have to think about this case:

find . -exec TURNIP{} {} +

It fits the rules for -exec ... +, but what to do about the {} in the 
command name "TURNIP{}".

--
Eric Blake   address@hidden    +1-801-349-2682
Libvirt virtualization library http://libvirt.org