Hi Victor,
> > > Saying 'do_something_interesting 2>&1 > something_interesting.log'
> >
> > Or, the alternative action of ‘foo >bar 2>&1’. :-)
>
> Now to me, it's more logical to tinker with the file descriptors of
> the command first and then say where they are going rather than vice
> versa.
But the order is significant. :-)
$ >foo
$
$ ls foo missing >out 2>&1
$ cat out
ls: cannot access 'missing': No such file or directory
foo
$
$ rm out
$ ls foo missing 2>&1 >out
ls: cannot access 'missing': No such file or directory
$ cat out
foo
$
> On a related note I recall early *nixes where the command switches had
> to precede all the other arguments.
That's also the POSIX standard today; see getopt(3p).
> Took me years to get used to the fact that in later versions you could
> say 'ls foo* -l'
This is a GNU extension and a bad idea. The Unix way is ‘ls -l -t foo
bar xyzzy’ that matches ‘verb adverbs nouns’. It means the reader can
stop on reaching the first non-option argument, knowing the rest are
data rather than options. And code can do that same, e.g. getopt().
Having an unnoticed option can be the cause of awkward bugs, even
dangerous ones depending on the command, and can come about through
command-line editing. If that option is treating as an argument, a
filename say, then that tends to have a lot less impact.
--
Cheers, Ralph.
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