sm-sorcery AT lists.ibiblio.org
Subject: Discussion of Sorcery related topics
List archive
- From: Jens Laas <jens.laas AT data.slu.se>
- To: Sergey A Lipnevich <sergeyli AT pisem.net>
- Cc: Dufflebunk <dufflebunk AT dufflebunk.homeip.net>, <sm-sorcery AT lists.ibiblio.org>
- Subject: Re: [SM-Sorcery]$IFS
- Date: Mon, 21 Oct 2002 15:12:31 +0200 (CEST)
(02.10.21 kl.08:09) Sergey A Lipnevich skrev följande till Dufflebunk:
Check this out:
a="a"
while read i ; do
a="${a}${i}"
echo $a
done < <(echo -e "a\nb")
# ^^^^^^^^^^^^^^^^^^^
echo "Final: $a"
Here is the output:
aa
aab
Final: aab
In this case i believe the (echo -e "a\nb") part runs in a subshell.
Cheers,
Jens
See my note on this in the ChangeLog. That's a harsh reality :-( of
bash, but it it possible to circumvent it in many specific cases.
Dufflebunk wrote:
>One odd side effect that I just found is that:
>echo $foo | while read i ; do
> #This is all executed in a sub shell!
>done
>
>Meaning environment modified inside the loop will not persist after the
>loop. Example:
>a="a"
>echo -e "a\nb" | while read i ; do
> a="${a}${i}"
> echo $a
>done
>echo "Final: $a"
>
>Here is the output:
>aa
>aab
>Final: a
>
>Not what you would expect. Although it makes sense when you look at it
>closely, it still surprised me, so I though it might help others too.
>
>
-----------------------------------------------------------------------
'This mail automatically becomes portable when carried.'
-----------------------------------------------------------------------
Jens Låås Email: jens.laas AT data.slu.se
Department of Computer Services, SLU Phone: +46 18 67 35 15
Vindbrovägen 1
P.O. Box 7079
S-750 07 Uppsala
SWEDEN
-----------------------------------------------------------------------
-
[SM-Sorcery]$IFS,
Sergey A. Lipnevich, 10/19/2002
-
Re: [SM-Sorcery]$IFS,
Dufflebunk, 10/19/2002
- Re: [SM-Sorcery]$IFS, Sergey A. Lipnevich, 10/20/2002
-
Re: [SM-Sorcery]$IFS,
Sergey A. Lipnevich, 10/20/2002
- Re: [SM-Sorcery]$IFS, Dufflebunk, 10/20/2002
-
Re: [SM-Sorcery]$IFS,
Dufflebunk, 10/21/2002
-
Re: [SM-Sorcery]$IFS,
Sergey A Lipnevich, 10/21/2002
- Re: [SM-Sorcery]$IFS, Jens Laas, 10/21/2002
-
Re: [SM-Sorcery]$IFS,
Sergey A Lipnevich, 10/21/2002
-
Re: [SM-Sorcery]$IFS,
Dufflebunk, 10/19/2002
Archive powered by MHonArc 2.6.24.