The question here, though, is why CGI's param method is returning a typeglob. Possibly the method performs differently in a string context?
...
CGI is probably giving you a filehandle...
That is it -- See (directed at OP) the 'CREATING A FILE UPLOAD FIELD' section in the CGI docs .. When the form is processed, you can retrieve the entered filename by calling param(): 
$filename = param('uploaded_file');

[download]
The filename returned is also a file handle.

So the split //, $var works because it's scalar context so is the filename.. Otherwise it must be treating it as a handle, and hence the observed error..

In reply to Re^2: CGI and Storable : explain me this, please. by davidrw
in thread CGI and Storable : explain me this, please. by lepetitalbert

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