Maybe. Where is that print exactly? Inside a function? If so, are you sure it is called? Maybe you can try warn instead of print, or even die, they print to STDERR rather than STDOUT so you should be able to see them in the console (and since die also stops the execution, if you use it and nothing changes, you're probably modifying code that actually never gets called). If you do see something with warn, you can search for select in the code, which will change the default output for print. But since you didn't manage to write to a file with an explicit filehandle for print, it's also probable that you are modifying code that isn't run.