I might be telling you the obvious... but have you checked that you actually have access to the device?  Which user are you running this as?  Can you send stuff to the device from the commandline (e.g. "echo foo >/dev/usb/lp0")?

For example, on my machine (Ubuntu), the /dev/usb/lp0  is being created as  (for example when I plugin my printer): 

$ ls -l /dev/usb/lp0
crw-rw---- 1 root lp 180, 0 2009-10-03 13:35 /dev/usb/lp0

[download]

but I'm not in group lp (by default), so I cannot access the device as my regular user. This is on purpose, because I'm not supposed to access the device directly, but rather go via the appropriate printing machinery, such as cupsd and friends.

In reply to Re: use Perl With usblp Parallel Adapter by almut
in thread use Perl With usblp Parallel Adapter by Morzilla

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