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From: Bob on 13 Oct 2009 09:29
Hi everyone,

I'm writing a PSCRIPT5 unidriver to be included in a printing auditing
system. The required feature is I need to insert current user's name,
host name and printing application (exe) into the PS stream for further
processing.

The driver should be usable both as a local printer and as a network
shared printer. The challenging part is that the client user may use a
different account to connect to the shared printer. So I cannot simply
write a graphics plugin to call GetUserName and insert the result in
IPrintOemPS::Command(Some commercial printer driver actually did this, btw).

My solution is to extend OEMDEV, putting the username into private
DEVMODE at UI plugin during IPrintOemUI::DevMode MERGE call and let
graphics plugin to do the output at the server end.

It works perfectly except one thing: user who prints printer test page
is not identified correctly. Further investigation shows this:
1. The UI plugin actually captures the user's name into DEVMODE.
2. The DEVMODE from UI plugin is not received by graphics plugin. I
looked into IPrintOemPS::DevMode calls and found the DEVMODE received is
not the one from UI, but the one kept in client's DevModePerUser
registry. Since I did not store user name into DEVMODE, graphics plugin
received null string.
3. If I delete the DevModePerUser key from client registry, the DEVMODE
received will be the "Default DevMode" from server's HKLM registry.
4. I rewrite IPrintOemUI::CommonUIProp to save user's name into DEVMODE
so system will keep it into registry, it temporarily solves the test
page problem. But later I find a bigger problem: if a user at the server
uses "Printer->Properties->Advanced->Printing Defaults" to create
default DEVMODE (with his user account inside), and a client user
deletes "DevModePerUser" key from client registry, then all the test
page printed will be credited to server's account. And I do not have a
way to differentiate "Printing Preferences..." and "Printing Defaults"
button.

I wonder what the test page did and why it does not use the standard way
to obtain DEVMODE. Is it by design and is there any walk rounds?

Thanks for reading that long.

Bob
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