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copied!<p>First off, the <code>tie</code> function returns the internal hidden object that represents the tie, and not the tied variable itself. Secondly, you can not return a plural tied value (hash or array) from a subroutine and have it work the way you are expecting. You need to return a reference to the plural value, and then dereference it when you need to use it.</p> <pre><code>use Config::IniFiles; sub config_file { tie my %cfg, 'Config::IniFiles', -file => 'settings.ini'; # tie variable return \%cfg; # return a reference to the tied variable } sub esx_host_check { my $esx_host = config_file()->{ESX}{host}; # call sub and dereference value } </code></pre> <p>If you are going to use the config hash more than a few times, its probably best to build it and then cache the result:</p> <pre><code>{my $cfg; sub config_file { tie %$cfg, 'Config::IniFiles', -file => 'settings.ini' unless $cfg; return $cfg; }} </code></pre> <p>This is a little different than above. First, we setup <code>config_file</code> to be a closure around the private variable <code>$cfg</code>. Note that it is a scalar and not a hash. Then in the sub, we check to see if the variable has been initialized, and if not, call <code>tie</code>. <code>tie</code> is passed a first argument of <code>%$cfg</code> which dereferences the undefined value as a hash, which has the effect of storing the tied hash reference into <code>$cfg</code>.</p> <p>While a little more complicated, this technique will only need to build the config hash once, potentially saving a lot of time.</p>

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