From:	AITGW::"MACRO32@WKUVX1.BITNET" 12-MAR-1992 18:00:47.95
To:	<EVERHART@ARISIA.DNET.GE.COM>
CC:	
Subj:	Re: Crude but quick

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Subject: Re: Crude but quick
Message-Id: <1992Mar12.212340.18726@rata.vuw.ac.nz>
From: <don@rata.vuw.ac.nz>
Reply-To: MACRO32@WKUVX1.BITNET
Date: Thu, 12 Mar 1992 21:23:40 GMT
References: <5647815@MVB.SAIC.COM>
Organization: Victoria University of Wellington
Lines: 25
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Apparently-To: <EVERHART@ARISIA.DNET.GE.COM>
 
The Silicon Sorcerer <FAGAN@FNAL.BITNET> writes:
>
>         .TITLE  MODIFY_IMAGE_HEADER
 
This is a new usage of the word "quick" I wasn't previously aware of?
 
How about:
 
$ open/read/write image 'p1'
$ read image header
$ header[%x20*8,1] = 1                                  ! Turn on debug bit
$ header[%x38*8,32] = f$cvui(%x34*8, 32, header)        ! Shuffle 1st & 2nd
$ header[%x34*8,32] = f$cvui(%x30*8, 32, header)        !   transfer addresses
$ header[%x30*8,32] = %x7FFEDF68                        ! Put traceback handler
$ write/update image header                             !   in 1st xfer address
$ close image
 
(I have a longer command file that will selectively tweak the debug bit
and traceback address, eg to turn off traceback so that an image can be
installed without resorting to a relink.)
 
--
Don Stokes, ZL2TNM (DS555)                      don@zl2tnm.gen.nz (home)
Network Manager, Computing Services Centre          don@vuw.ac.nz (work)
Victoria University of Wellington, New Zealand.           +64-4-495-5052
