Path: utzoo!mnetor!uunet!lll-winken!lll-tis!ames!mailrus!tut.cis.ohio-state.edu!ut-sally!utah-cs!utah-gr!uplherc!sp7040!obie!wsccs!terry
From: terry@wsccs.UUCP (terry)
Newsgroups: comp.unix.xenix
Subject: Re: no peek or poke under xenix?
Message-ID: <258@wsccs.UUCP>
Date: 4 Mar 88 08:41:45 GMT
References: <284@dcdwest.UUCP>
Lines: 21
Keywords: xenix
Summary: Peek and Poke in UNIX and Xenix

In article <284@dcdwest.UUCP>, phb@dcdwest.UUCP (Peter H. Berens) writes:
> We have a device driver for a memory mapped device that crashes the
> system when the board is not installed in the system and someone opens
> the device node.  We would like to be able to use peek or poke in the
> open routine to determine if the memory addresses the board responds
> to are present

	Use a setuid(geteuid()) root program (chmod 4755) to open /dev/mem
and lseek() to your offset location.  Then just read.

			:-)

PS: This is a nifty way to put one of thos damn clocks in the upper-right
hand corner of your screen... just write to the upper right-hand corner.


| Terry Lambert           UUCP: ...!decvax!utah-cs!century!terry              |
| @ Century Software       or : ...utah-cs!uplherc!sp7040!obie!wsccs!terry    |
| SLC, Utah                                                                   |
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