if u
var=value command ;
the var's only for cmd and disappears afterwards
if u
var=val ; cmd ;
its not for cmd , excepts exported
and is set after cmd , usual behav
old rule
On Thu, May 23, 2024, 3:34 PM Robert Elz wrote:
> Date:Thu, 23 May 2024 09:04:48 -0400
> From:
Date:Thu, 23 May 2024 09:04:48 -0400
From:Chet Ramey
Message-ID:
| The bash output clearly tells you the
| order of operations, which is the whole purpose of -x.
But it can be horribly misleading. Consider what bash does with
this similar case (I used 5.3a1
On 5/22/24 10:57 PM, Oğuz wrote:
And some Bourne shells expand command substitutions first
$ (exit 5)
$ x=$? y=`exit 10`
$ echo $x
10
It's worse than that. The v7 sh performed assignments right to left.
--
``The lyf so short, the craft so long to lerne.'' - Chaucer
``Ars
On 5/22/24 6:56 PM, Dan Jacobson wrote:
It seems these should both make one line "+ a=b c=b" output,
for s in sh bash
do $s -xc 'a=b c=$a'
done
I mean they give the same results, but bash splits it into
two lines, so the user reading the bash -x output cannot tell
if one (correct) or two
Date:Thu, 23 May 2024 05:57:05 +0300
From:=?UTF-8?B?T8SfdXo=?=
Message-ID:
| On Thu, May 23, 2024 at 2:49 AM Steffen Nurpmeso wrote:
| > Only to note that this is not portable.
| Nor will NetBSD sh.
That's right, and this is expressly unspecified in POSIX.
On Thu, May 23, 2024 at 2:49 AM Steffen Nurpmeso wrote:
> Only to note that this is not portable.
> The FreeBSD shell will not assign "b" to "c" for this one!
Nor will NetBSD sh. This lets you swap values of two variables without
using a third
$ x=1 y=2
$ x=$y y=$x
$ echo $x $y
2 1
And some
Greg Wooledge wrote in
:
|On Thu, May 23, 2024 at 06:56:01AM +0800, Dan Jacobson wrote:
|> It seems these should both make one line "+ a=b c=b" output,
|>
|> for s in sh bash
|> do $s -xc 'a=b c=$a'
Only to note that this is not portable.
The FreeBSD shell will not assign "b" to "c" for
On Thu, May 23, 2024 at 06:56:01AM +0800, Dan Jacobson wrote:
> It seems these should both make one line "+ a=b c=b" output,
>
> for s in sh bash
> do $s -xc 'a=b c=$a'
> done
>
> I mean they give the same results, but bash splits it into
> two lines, so the user reading the bash -x output
It seems these should both make one line "+ a=b c=b" output,
for s in sh bash
do $s -xc 'a=b c=$a'
done
I mean they give the same results, but bash splits it into
two lines, so the user reading the bash -x output cannot tell
if one (correct) or two (incorrect) lines were used.
They can tell with
