>>>I want to write data to lpt1 port to control PCU customer display.
>>>The only way to do using vfp native commands is "run copy fn lpt1"
>>>but this is too low for disply control.
>>>
>>>So the only possibility is to use API.
>>
>>Did you try COPY FILE (filename) TO LPT1:
>
>I run (w95 osr2, vfp build 415)
>
>copy file c:\autoexec.bat to lpt1
>
>a message
>
>c:\vfp\lpt1 already exists, overwrite it?
>
> appears
>If i choose Yes, an Invalid seek offset error occurs!
>
>Only
>
>!copy file c:\autoexec.bat to lpt1
>
>works, but this is TOO slow for PCU display and requires lpt1 to be captured.

It's not a problem to remove 'overwrite' message (SET SAFETY), but Invalid offset signals something more serious. I use this way to print reports from files.