Get variable value

[Jboy123]

Hi

I'm having a problem where a variable is not being interpreted instead the name of the variable is being displayed.

sub one
{
# Some code here that sets following variable
$wcnode="avalue"
}
sub two
{
$hostname=myhost;

#Read in a config file with key/value pairs separated by '='
foreach $line (@configfile)
{
($key, $value) = split(/\=/, $line);
chomp($key);
chomp($value);
%myhostnameHash->{$key} = $value;
}
# Then set a variable that is equal to a variable defined earlier in script
$installdir = "$myhostnameHash{$hostname}";
print "Value of installdir is $installdir\n";

}

# Main
&sub_one;
&sub_two;

$configfile is a flat text file that contains e.g. the following:

myhost=$wcnode

When I call the print statement in 'sub two' what is returned is:
$wcnode
Instead of the value of $wcnode - 'avalue'

I've set a variable to another variable many times before without any problems. E.g $x = $y

Is there something I need to do to to evaluate the variable??

Any help appreciated
Thanks!

 

[arn0ld]

try "use strict" to double-check code
what is "myhost" ?

 

[Jboy123]

Hi

Tried use strict but just got back a page full of messages along lines of:

Global symbol "$variable" requires explicit package name at ./myscript.pl line 46.

Is ther something I should be looking for?

$hostname = "myhost";
myhost is just a value.

Thanks

 

[teriviret]

I noticed in your script you have this:

%myhostnameHash->{$key} = $value;

Shouldn't that be this?

$myhostnameHash{$key} = $value;

 

[Jboy123]

Thanks Teriviret

Both seem to work.

$myhostnameHash{$key} = $value;
%myhostnameHash->{$key} = $value;

This is the first time I've been playing around with hashes so I'm not really sure what the difference in the two lines is.

When I retrieve the key from the has the correct value is returned - the problem remains that I want that value to be a variable name which when I use it later in the script the variable is not being interpreted - just the name is returned (in the print statement).

 

[teriviret]

It sounds like you want to de-reference a symbolic reference. Something like this?

$abc = '123';
$def = 'abc';
print "$abc\n";  # prints:  123
print "$def\n";  # prints:  abc
print "$$def\n"; # prints:  123

 

[Jboy123]

Hi

I'm still getting the same issue:

I think the problem is with :

# Then set a variable that is equal to a variable defined earlier in script
$installdir = "$myhostnameHash{$hostname}";
print "Value of installdir is $installdir\n";

What I want to achieve is:

$installdir = $wcnode; # Where $wcnode is a variable previously defined in the script with a value of, for example, 'avalue'.

The value for the key $myhostnameHash{$hostname} is actually a string value of $wcnode. I sucessfully reteive this from the hash. But my problem is that $installdir gets a value of the string $wcnode not the actual value of the variable $wcnode i.e. 'avalue'

Does this make any more sense?

Thanks

 

[Jboy123]

Okay

Got it to work by using eval

$installdir = eval "$myhostnameHash{$hostname}";

Thanks for your help.