Re: zargs doesn't work reliably

["Mikael Magnusson" <mikachu@gmail.com>]

On 8/18/06, Bart Schaefer <schaefer@brasslantern.com> wrote:
> On Aug 17,  3:59pm, Mikael Magnusson wrote:
> }
> } Usage: zargs [options --] [input-args] [-- command [initial-args]]
> }
> } % touch -- -- -+
>
> There are approximately eleventeen zillion unix/linux commands that
> break given those file names, including rm, ls, and cp, so I'm not
> going to get particularly worked up about zargs behaving similarly.

% ls -l -- *
-rw-r--r-- 1 mikaelh users 0 2006-08-18 00:55 -+
-rw-r--r-- 1 mikaelh users 0 2006-08-18 00:55 --

> However, if you'd looked just a little further, you'd find that in
> fact zargs already has a solution for this problem.  There is even
> an example in the manual:
>
>      In the event that the string `--' is or may be an INPUT, the -e
>      option may be used to change the end-of-inputs marker.  Note that
>      this does _not_ change the end-of-options marker.  For example, to
>      use `..' as the marker:
>
>           zargs -e.. -- **/*(.) .. ls -l
>
>      This is a good choice in that example because no plain file can be
>      named `..', but the best end-marker depends on the circumstances.
>
> (End manual page example, begin new one.)  You can even do:
>
>           zargs -e$'\0' -- * $'\0' ls -d
>
> unless you somehow have a file named (the nul byte).
>
> } since input-args is the only part you do not control
>
> The only part who does not control?

What i meant was it's the only part of the command that may contain
unplanned -- instances. Unless you also glob somewhere else in the
command... but that seems like a bad idea?

> } it should come last, like so
> } Usage: zargs [options --] [command [initial-args]] -- [input-args]
>
> I think the designers of the xargs command, after which zargs is closely
> modeled, would disagree with you.  See "man xargs".
>
> } A problem is how to give -- as initial-args then

Would this be possible?
zargs '[options]' 'command [initial-args]' [input-args]
ie the ' are literal quotes in the command so zargs knows exactly what
to do with the first two arguments (in which case you'd have to zargs
'' '' * if you wanted to omit them so maybe not aesthetically pleasing
in that regard).

> Precisely.  Another problem is that the command and initial-args may be
> omitted, but the input-args may not be.

Sorry, I should have looked in the manual. In my defense zargs --help
was so helpful that i didn't suspect it left anything useful out and i
did say i was tired :). Thanks for the pointers.

-- 
Mikael Magnusson