Re: Comparing strings

From: ELCV (clsamc...)

> Try changing your ssh command to be:
>
> ssh [email protected] dd of=/backup/images/${ARG}_0.img
>

That works! Thank you again.

On Wednesday, July 14, 2021 at 11:58:17 AM UTC-4, Grant Taylor wrote:
> On 7/14/21 9:42 AM, ELCV wrote:
> > A new issue. I am evaluating my script so I am using echo to display
> > the commands.
> >
> > My function is as follows:
> > singleVolume(){
> > # OS Volumes
> > echo "virsh suspend $ARG"
> > echo "dd if=/dev/vg0/$ARG_0 | ssh [email protected] dd of=/backup/images/$ARG_0.img"
> > echo "virsh resume $ARG"
> > }
> >
> > When I run my command the $ARG variable in the second line is not echoed:
> >
> > virsh suspend FOO
> > dd if=/dev/vg0/ | ssh [email protected] dd of=/backup/images/.img
> > virsh resume LIMS2
> >
> > So the variable and the _0 are being dropped. I've tested without
> > "echo" and obtained the same result.
> >
> > If I create a new variable, SUFF="_0" and then use echo
> > "dd if=/dev/vg0/$ARG$SUFF | ssh [email protected] dd
> > of=/backup/images/$ARG$SUFF.img"
> >
> > It works. Is this expected? It only seems an issue using functions.
> I don't know if I would /expect/ it per se or not. But I am not at all
> surprised by it.
>
> This hints at an escaping problem to me. Maybe. Maybe not.
>
> Try changing your ssh command to be:
>
> ssh [email protected] dd of=/backup/images/${ARG}_0.img
>
> Avoid the abiguity of what is variable vs appended string.
>
> Aside: That might not be the escaping that I was referring to as
> escaping would usually be how your local shell interprets $ARG, or not,
> prior to sending it to the remote shell / sub-command. Escaping is more
> about where the expansion should happen. And I think your primary /
> current issue is what is the variable vs data.
>
> > Thanks.
>
> You're welcome.
> --
> Grant. . . .
> unix || die

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Comparing strings... by ELCV on Jul 13th 2021, 17:46
Re: Comparing strings... by Grant Taylor on Jul 13th 2021, 20:29
Re: Comparing strings... by ELCV on Jul 14th 2021, 01:53
Re: Comparing strings... by ELCV on Jul 14th 2021, 15:42
Re: Comparing strings... by Grant Taylor on Jul 14th 2021, 15:58