File I/O in kernel module

Stefan Fischer (stefan.fischer@mrc-heidelberg.de)
Thu, 6 May 1999 16:08:48 +0200 (MEST)


Hallo,
we are working on a pressure control system, which has to control 2 pumps
over a serial lines (RS232) an to measure a pressure sensor over the
parallel port.
The control algorithm should run as a RT-task as a kernel module.
So this modules has to communicate with the serial lines.
Compiling it as a userspace program works fine unless the timing accuracy.
As a kernel module the symbols
open, close, write, read ...
are unresolved unless static linking against libc.a,
but then the symbols
__udivdi3 and __umoddi3
are undefined.
Is there a general problem with the use of file i/o in kernel modules,
or is the libc.a (ver 5.4.33?) to old?

Thanks in advance

Stefan Fischer

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Stefan Fischer
MRC Systems GmbH
Czernyring 22/11 phone:+49(0)6221 13803-18
69115 Heidelberg fax: +49(0)6221 13803-01
Germany email:stefan.fischer@mrc-heidelberg.de
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