From:	SMTP%"nowicki@tardis.larc.nasa.gov" 27-MAY-1994 14:53:07.63
To:	EVERHART
CC:	
Subj:	Help with AXP shared images

From: nowicki@tardis.larc.nasa.gov (Gregory D. Nowicki)
X-Newsgroups: comp.os.vms
Subject: Help with AXP shared images
Date: 26 May 1994 20:34:10 GMT
Organization: NASA Langley Research Center
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To: Info-VAX@CRVAX.SRI.COM
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I am posting this for a co-worker.  If you have any idea on how to solve 
this, please contact me, Susan, or post it to USENET.  Thanks.

SEEKING ENLIGHTENMENT ON ALPHA Shared Images

I am attempting to create and install a shared image on an Alpha
workstation running OpenVMS V1.5-1H1.  The same procedure that works fine
on a VAX will not work on the Alpha.  The program will compile, link and
run with no error messages but the variables in the shared image have an
initial value of zero each run.  So it is obviously changing just a local
copy of the variable instead of the global one intended.  I noticed that
the fortran listing file on the VAX shows the common block SHARED as having
the SHR attribute while the listing file on the Alpha shows it with NOSHR.
So I'm suspecting some difference between the two FORTRAN compilers or I'm
using an incorrect linker option, but don't know where to go from here. 

I have included listings of the shared image, how it was created, and the
test program. 

Please let me know if you have encountered and solved this problem or have
any suggestions of where to find a solution. 

Thanks,
Susan Kooi
s.a.kooi@larc.nasa.gov

SHARED IMAGE SOURCE CODE
------------------------
program shareit
byte		flag
common /shared/ flag
end

SHARED IMAGE CREATION
---------------------
$ for/lis shareit	
$ link/map/full/share shareit
$ install add /header/share/write sys$library:shareit.exe

TEST PROGRAM SOURCE CODE
------------------------
program test_share1
byte		flag
common /shared/ flag
print*,' inital value flag = ',flag
flag = 99
print*,' end value flag = ',flag
end

program test_share2
byte		flag
common /shared/ flag
print*,' flag = ',flag
end

TEST PROGRAM RUN
----------------
$ define shareit sys$library:shareit.exe
$ for/list test_share1
$ link test_share1,sys$input/opt
shareit/share
^Z
$ for/list test_share2
$ link test_share2,sys$input/opt
shareit/share
^Z
$ r test_share1
$ run test_share1
 inital value flag =     0
 end value flag =    99
$ run test_share2
 flag =     0
$

-Greg

/* Greg Nowicki | Mail Stop 401A | LIDAR Applications Group */
/* NASA Langley Research Center  | Hampton, Virginia  23681-0001 */
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