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dbm file locking with different versions of perl

Hello,

Recently we made some fairly significant upgrades...goin g from Solaris 5.6
to Solaris 5.8 (Solaris 8). Along with this, we decided to upgrade from
perl 5.005_03 directly to perl 5.6.0. Although this was a fairly
significant jump (especially in perl versions), our applications are such
that the testing was fairly straight-forward and we did not run into many
problems. However, I've run into one that I hope to find some answers to.

We have one application that uses a series of dbm files for data storage.
The dbm file is opened using "dbmopen(my %dbm, $dbm, undef)". Under the old
operating system and version of perl, everything ran fine. In fact,
everything runs fine under the new scenario except when simultaneous
executions of the script access the same dbm file (this worked before). We
get a "Resource is temporarily unavailable" error message on the second
execution and the second execution fails. The first finishes without
problem. Once the first has finished another can be run without problem.

My guess is that something has changed in either the new OS or in the new
version of perl with how the dbm files are managed/locked. In order to test
this, I reverted back to 5.005_03 on the new OS and am still able to
reproduce these results...so I'm now thinking that the OS is not the culprit
but something in how perl 5.6.0 (or another version post 5.005_03) handles
dbm files. The jump from 5.005 to 5.6.0 is fairly big so I'm not sure if it
is a change in 5.6.0 itself or just something new to us since that is our
next version. We made the jump to better be able to handle unicode support
as it evolves. I am planning on upgrading 5.6.0 fairly soon but need to
resolve this issue first.

Any thoughts on what happened and possible solutions would be greatly
appreciated! Thanks.

Matt
Jul 19 '05 #1
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