> AFAIK, the name EMMXXXX0 is part of the EMS> standard, meaning any EMS
> manager MUST use> use this device name. If you read the EMS v4 spec carefully
> (http://www.phatcode.net/res/218/files/limems40.txt), it doesn't actually say
> that the EMMXXXX0 name is required. It's mentioned in the appendices that
> provide two examples of how to test for EMS. How the text is worded in the
> appendices merely IMPLIES that the name should be EMMXXXX0, but the
> specification never actually says that it MUST be. I don't think I've ever
> seen an earlier version of the spec, and the earlier versions may say
> something completely different. Also, if you scan RBIL for "EMMX", you find
> references to at least three other names that are associated with EMM's:
> 386MAX$$, QMMXXXX0, & EMMQXXX0. I don't actually know if any of those are
> legitimate alternative names or not, but because they are associated with
> EMM's in RBIL don't think you can simply ignore them. In the appendices, it
> also talks about when you can and can't use the Device Name method and MUST
> use the INT 67h method that I outlined briefly (but is fully described in the
> specification). Plus, the Device Name method is actually bigger and slower
> than the INT 67h method. So, the Device Name method is bigger, slower, less
> reliable, and less universal/portable than the INT 67h method, so I
> personally see no value in ever using it at all, and in my programs I don't.
> > Also, there are some fastidious recommended> tests for detecting an EMS
> manager, both in> official (MS DOS Encyclopedia) and unofficial> (Ray
> Duncan's "Extending DOS") literature.> Either use, as a first step, the
> detection of> a file or device named EMMXXXX0 in the current> working
> directory and does not proceed if none> is found. To that I would say that
> they may not have actually read the EMS specification, because it certainly
> doesn't say that. The spec says you can use either the Device Name or INT
> 67h method, but it doesn't say you MUST look for the Device Name. There's
> also the issue of the fact that an EMM doesn't actually need to be installed
> as a device driver in CONFIG.SYS, so doesn't really even NEED to have a
> device name at all. Japheth's JEMM can be installed as a TSR instead of a
> device driver, for example. He installs a device driver name to make JEMM
> compatible with programs that (erroneously) assume a device driver named
> EMMXXXX0 must exist or EMS memory can't exist. The device name has NOTHING to
> do with using EMM in DOS. In order to install a device driver via
> CONFIG.SYS, the driver must either have a name (if it is a character device)
> or will be assigned one or more drive letters (if it is a block device). For
> some devices, the name is actually useful and you can redirect things to/from
> it (NUL, LPT1, CON, etc.). In the case of an EMM, the name can't be used for
> redirection and is really only there because installing a character device in
> CONFIG.SYS requires a name. All of the interesting and useful stuff for an
> EMM happens with INT 67h. However, as discussed in RBIL, the EMMXXXX0 name is
> required for EMM's that are compatible with Windows. An EMM "transforms"
> itself and works differently when Windows starts so that Windows can handle
> the EMS instead of the EMM doing it, and then must revert back to normal when
> Windows closes (this is for older versions of Windows that could be shut down
> without rebooting). I think M$ was the only one who ever made an EMM that
> was fully compatible with Windows. I know Qualitas tried to make one and was
> fairly successful, but am not sure exactly how far that got.
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