To: pgsql-hackers@postgresql.org
From: Thomas Hallgren <thhal@mailblocks.com>
Subject: Use of zlib
Date: Thu, 23 Sep 2004 13:02:17 +0200
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Message-ID: <ciuafp$n4u$1@sea.gmane.org>
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Problem:
PL/Java use a JVM. On some platforms and with some JVM's (Sun's in 
particular) a libzip.so is bundled that contains a 1.1.3 version of 
functions also provided in zlib (why they do this is beyond me, but they 
do so I'll have to live with it). PostgreSQL is linked with zlib by 
default. This resuls in a conflict which resuls in a JVM crash.

I can circumvein this crash by using LD_PRELOAD to force a load of the 
JVM bundled libzip.so but I suspect that might result in a crash as soon 
as PostgreSQL calls on zlib to do something. It's of course possible to 
configure postgresql with --without-zlib also provided you have accesst 
o the source.

Question:
 From what I can understand from the documentation, the only utility in 
PostgreSQL that actually uses zlib is pg_dump? If so, why is the 
postgres process linked with -lz?

Regards,

Thomas Hallgren