On Linux (currently testing RHEL6.5), it appears that LD_LIBRARY_PATH must be defined/exported *outside* my script in order to load DBD::Oracle successfully. This is not so on AIX (LIBPATH), and I wasn't expecting it on Linux either. Setting $ENV{LD_LIBRARY_PATH} in a BEGIN block at the top of my script gets the standard

install_driver(Oracle) failed: Can't load '/home/jrw/perl_dbi/linux/li
+b/perl5/x86_64-linux-thread-multi/auto/DBD/Oracle/Oracle.so' for modu
+le DBD::Oracle: libclntsh.so.18.1: cannot open shared object file: No
+ such file or directory at /usr/lib64/perl5/DynaLoader.pm line 200.
 at (eval 38) line 3
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whereas exporting LD_LIBRARY_PATH *before* running perl -e allows the script to succeed. Does DynaLoader cache the initial LD_LIBRARY_PATH during script startup? Or is something else going on? Test script:

export DIR=/home/jrw/perl_dbi/linux

unset LD_LIBRARY_PATH
# export LD_LIBRARY_PATH=$DIR/oracle_instantclient

perl -e '
   use strict;
   use warnings;
   BEGIN { $ENV{LD_LIBRARY_PATH} = "$ENV{DIR}/oracle_instantclient" }
   use lib "$ENV{DIR}/lib/perl5";
   use DBI;

   my @drivers = DBI->available_drivers;
   print "Drivers = @drivers\n";
   foreach my $driver (@drivers) {
      my @databases = DBI->data_sources($driver);
      print "   Driver: $driver, data sources = @databases\n";
   }
'
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