Path: utzoo!utgpu!cunews!bnrgate!brchh104!brchs1!bnr.ca!rice.edu!sun-spots-request
From: iapsd!hopi!glenn@uunet.uu.net (Glenn Herteg)
Newsgroups: comp.sys.sun
Subject: Re: Strange behaviour of /dev/mem
Keywords: Miscellaneous
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Date: 24 Apr 91 00:00:00 GMT
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| However, on SLC, IPC and SS1+ machines here, the result is always exactly
| 4Meg regardless of the amount of physical memory the machines have!

RTFM, *carefully*!:

mem is a special file that is an *image of the physical memory* of the computer.

Some machines may not have contiguous physical memory, to allow for
different sizes of SIMMS to be plugged in.  Probably there is a "hole"
after the first 4 Meg, and reading /dev/mem in a continuous stream finds
an apparent EOF when it tries to read a hole.