Re: xargs feature request...

[Andreas Metzler]

On 2005-04-16 "Linda A. W." <address@hidden> wrote:

> It would be nice if xargs had an option to enclose the arguments it reads
> in in either double or single quotes before passing them to a program.

> This would be especially useful for files with "spaces" in them.
> :-)
[...]

Actually it would not. ;-)

For dealing with filenames with spaces you need quotes to keep the
shell from splitting the input and passing the name as a single
argument to the program.

e.g. for
/tmp$ /bin/ls "with space"
the shell invokes /bin/ls with the single argument »with space«
(without the quotes!), while for
/tmp$ /bin/ls with space
the shell would split at the space and invoke  /bin/ls with the two
arguments »with« and »space«.

However when xargs _invokes_ programs there is no shell involved
echo foo | xargs ls
causes ls to be run with arguments foo, if xargs added quotes this
fail horribly, as there is no file named "foo" (with quotes).

It is the other way round, you have to keep _xargs_ from splitting
_its_ _own_ input:
/tmp$ echo 'with space' | xargs ls
ls: with: No such file or directory
ls: space: No such file or directory
if you manage that xargs does not need to add quotes, as it does not
invoke a shell:
--------
/tmp$ echo "'with space'" | xargs ls
with space
--------

So you actually do not need to adapt xargs, but the program that
generates the input for xargs.

Usually that is find, and
find -some -criteria -print0 | xargs -r0 some_program
works wonderfully with as insane filenames as you can imagine.
               cu andreas
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