isapi extension

currently i'm using visual c++ 6.0 to create isapi extension. i face a problem to locate my _outp() command. where should i locate it in the program? it will receive the number sent by the user and output it to parallel port at the server side. is it can't be located under on_parse_command() function which has the CHttpServerContext?
deric19Asked:
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jhanceCommented:
_outp() is not possible from an ISAPI extension.

This is a protected mode instruction on WIN32 and can only be run by a program which is running in RING0.  That means it's a DEVICE DRIVER on NT or a VxD on Win9x.

Since you're talking about ISAPI, I'll have to assume your also talking about NT Server running IIS.  That leaves you with the following possibilities:

1) If you need to directly control the parallel port, get or write a parallel port device driver that has the functionality you need and install it.  Now you can open it from your ISAPI with CreateFile() and then you can control it with DeviceIoControl().

2) If you just need the functionality of the standard parallel port (i.e. the printer driver function) you can open the standard parallel port with CreateFile() and output to it with WriteFile().
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deric19Author Commented:
jhance,

   thanks for the answer. but i'm just a greenhorn in using isapi, can u give a some guide or example how to use CreateFile() and DeviceIoControl() to control my parallel port in NT server running IIS. Thanks again for the advise.
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