Re: [PLUG] Splitting strings in bash

[JP Vossen via plug <plug@lists.phillylinux.org>]

On 4/26/23 04:09 PM, Walt Mankowski wrote:
> On Wed, Apr 26, 2023 at 04:00:24PM -0400, JP Vossen wrote:
> > On 4/26/23 03:46 PM, Walt Mankowski via plug wrote:
> > > Hi all,
> > >
> > > I've got a question about splitting strings in a bash shell
> > > script. Let's say I've got a string
> > >
> > > STR='dog cat'
> > >
> > > I'd like to split that on the space into two variables, foo and bar. I
> > > tried this
> > >
> > > echo $STR | read foo bar
> > >
> > > but it doesn't work. On the following line foo and bar are back to
> > > their original values. Then, after looking through the bash manpage
> > > for an alternative, I tried this instead
> > >
> > > read foo bar <<< $STR
> > >
> > > That DID work!
> > >
> > > So that solves my problem, but I'm still confused. Those two commands
> > > seem to me like they should be identical. Why doesn't the first one work?
> >
> > Because the `|` causes a sub-shell, which cannot modify the environment in the parent shell.  That's frustrating as hell, and causes subtle little things like you ran into a lot. :-/
>
> Thanks! It makes sense after I thought about it for a bit.
>
> BTW did you mean to just send this to me instead of the list?

No, I meant the list.  It's been a LONG week already...

Later,
JP
--  -------------------------------------------------------------------
JP Vossen, CISSP | http://www.jpsdomain.org/ | http://bashcookbook.com/

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