Pass Varialbe into Backtick Operation

[utahcon]

Hey all I am trying to run a script ot the shell like this.

$output = `uzip path/path/path/file`;
echo $output;

What I need to do is pass a variable into this.

How do I do that?

The ` is a tick (next to the 1) not a single quote.

everytime I try to do this I get a parse error.

Here is what I have tried

$output = `unzip /path/path/path/$_POST['file']`;
echo $output;

$output = `unzip /path/path/path/" . $_POST['file'] . "`;
echo $output;

also tried with single quotes

Any help?