Re: LINUX is obsolete
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Re: LINUX is obsolete
in article <12605@star.cs.vu.nl>, ast@cs.vu.nl (Andy Tanenbaum) says:
> The drivers have to read and write the device registers in I/O space, and
> this cannot be done in user mode on the 286 and 386. If it were possible
> to do I/O in a protected way in user space, all the I/O tasks could have
> been user programs, like FS and MM.
The standard way of doing that is to trap on i/o space protection
violations, and emulate the i/o for the user.
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BURNS,JIM (returned student)
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