trouble when calling a shell script for setting an env var

[Paul Johnson]

On Thu, Jan 16, 2003 at 08:58:22PM +0100, Konrad Foerstner wrote:

> I need to get a value from an environment variable VALUE. This value is
> set by an shell script which location is stored in anonther environment
> variable called SCRIPT. So I first call the shell script by
>
> `. \$SCRIPT`;
>
> and extract then the value of VALUE by
>
> my $value = $ENV(VALUE);
>
> But something does not work, so $value is empty. As the shell script
> produces also an echo output I catch it by using
>
> my @output = `. \$SCRIPT`;
>
> I get this output correctly, but VALUE is still empty! I also tried also
>
> system(\$SCRIPT`);
>
> and
>
> `. /place/of/my/shellscript.sh`;
>
> Both don't have the wished effect.
>
> When I call the shell script in the shell and the start my perl script
> VALUE is set and available for my perl script.
>
> What is wrong?

Unfortunately, your understanding of processes. A child process cannot
alter the environment of its parent.

Take a look at Shell::Source on CPAN.

--
Paul Johnson - pa...@pjcj.net
http://www.pjcj.net

[Konrad Foerstner]

He folks!

Todays problem:

I need to get a value from an environment variable VALUE. This value is
set by an shell script which location is stored in anonther environment
variable called SCRIPT. So I first call the shell script by

`. \$SCRIPT`;

and extract then the value of VALUE by

my $value = $ENV(VALUE);

But something does not work, so $value is empty. As the shell script
produces also an echo output I catch it by using

my @output = `. \$SCRIPT`;

I get this output correctly, but VALUE is still empty! I also tried also

system(\$SCRIPT`);

and

`. /place/of/my/shellscript.sh`;

Both don't have the wished effect.

When I call the shell script in the shell and the start my perl script
VALUE is set and available for my perl script.

What is wrong?

Konrad

[Konrad Foerstner]

> > I need to get a value from an environment variable VALUE. This value is
> > set by an shell script which location is stored in anonther environment
> > variable called SCRIPT. So I first call the shell script by
> >
> > `. \$SCRIPT`;
> >
> > and extract then the value of VALUE by
> >
> > my $value = $ENV(VALUE);
> >
> > But something does not work, so $value is empty. As the shell script
> > produces also an echo output I catch it by using
> >
> > my @output = `. \$SCRIPT`;
> >
> > I get this output correctly, but VALUE is still empty! I also tried also
> >
> > system(\$SCRIPT`);
> >
> > and
> >
> > `. /place/of/my/shellscript.sh`;
> >
> > Both don't have the wished effect.
> >
> > When I call the shell script in the shell and the start my perl script
> > VALUE is set and available for my perl script.
> >
> > What is wrong?
>
> Unfortunately, your understanding of processes. A child process cannot
> alter the environment of its parent.
>
> Take a look at Shell::Source on CPAN.

Ah, okay! Thanks a lot!
Konrad