Date: Sun, 23 Dec 2012 16:52:08 +0100 From: =?UTF-8?B?76O/IERow6luaW4gSmVhbi1KYWNxdWVz?= <dhenin@gmail.com> To: Polytropon <freebsd@edvax.de> Cc: FreeBSD Global Users Mailing List <freebsd-questions@freebsd.org>, Jack Mc Lauren <jack.mclauren@yahoo.com> Subject: Re: shell script problem Message-ID: <CAL5Cjnx7CdTbAm=LMWDvnoiphQRMKOJKXm7ypVZ3wFrJ7i1g_w@mail.gmail.com> In-Reply-To: <20121223104311.557f3752.freebsd@edvax.de> References: <1356253535.76738.YahooMailClassic@web160101.mail.bf1.yahoo.com> <20121223103434.def7cd9c.freebsd@edvax.de> <20121223104311.557f3752.freebsd@edvax.de>
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2012/12/23 Polytropon <freebsd@edvax.de>
> On Sun, 23 Dec 2012 10:34:34 +0100, Polytropon wrote:
> > First, the lines with "read" have to be:
> >
> > cat /foo/bar.txt | while read $LINE1
> >
> > cat /foo/bar/foo/bar.txt | while read $LINE2
> >
> > Reason: $LINE1 and $LINE2 will be evaluated here, they are "empty
> > string", causing "read" to throw an error.
>
> Excuse me - I made a mistake! Of course those two lines
> have to be:
>
> cat /foo/bar.txt | while read LINE1
>
> and
>
> cat /foo/bar/foo/bar.txt | while read LINE2
>
> The $ infront of the variable names have to be removed.
> The variable _name_, not its content, has to be provided
> to "read" as a parameter.
>
> The script so far:
>
>
>
> #!/bin/sh
>
> cat foo.txt | while read LINE1
>
* echo "Pid Process: " $$*
> do
> cat bar.txt | while read LINE2
> do
> if [ "$LINE1" = "$LINE2" ]; then
> sw="1"
> echo "Current value of sw is : " $sw
>
*ps -ax |grep bar *
> break
> fi
> done
> echo "Value of sw is : " $sw
> if [ "$sw" = "0" ]; then
> echo "DO SOMETHING!"
> fi
> sw="0"
> done
>
Has you can see, "pipe" make a subshell and sw is lost.
Hope this help
---------------------------------------------------------
(°> Dhénin Jean-Jacques
/ ) 48, rue de la Justice 78300 Poissy
^^ dhenin@gmail.com
---------------------------------------------------------
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