[redland-dev] Using Perl Bindings on Shared Host

[Dave Beckett]

On Fri, 19 Aug 2005, Chris Murphy wrote:
> Hello,
> I've written a simple perl script using the librdf bindings, and it works 
> fine (and as expected) from the shell. My problem is that I am attempting to 
> use it as a CGI, on a shared webhost. That host did not have redland 
> installed, so I compiled it from source, along with the bindings. The 
> problem is that initially the script refuses to run at all, citing that it 
> can't find RDF/Redland.pm as expected. I solved this problem by adding some 
> -I /home/myStuff/... parameters to the shebang line.
> 
> The problem that eventually stops me dead in my tracks is that DynaLoader 
> doesn't seem able to find librdf.so.0 when it goes to load the CORE modules 
> (specifically on line 7 of CORE.pm). I've tried putting the path in a -I 
> parameter, I've tried setting LD_LIBRARY_PATH in the environment, I've tried 
> playing with @dl_library_path for DynaLoader, though I'm sure I wasn't doing 
> that correctly. I'm not 100% sure that I've successfully set LD_LIBRARY_PATH 
> for the cgi, but I've tried several times, including a few ways inside of 
> the perl script itself (before use 'RDF::Redland'). Does anybody know the 
> 'right' approach to solving this?

What you probably need is a BEGIN block - which runs before 'use' happens, 
as it's part of the perl compile/interpret stage.

Something like (untested, copying from somewhere else):

BEGIN {
  $ENV{'LD_LIBRARY_PATH'}='/path/to/lib';
  unshift(@INC, "/path/to/prefix/lib/perl5/site_perl/5.8.4/i386-linux");
  unshift(@INC, "/path/to/prefix/lib/perl5/site_perl/5.8.4");
}

use RDF::Redland;
...


you can probably tweak the oaths


> Again, the script works fine from the command prompt by setting 
> LD_LIBRARY_PATH, but I can't make it work as a CGI. I'm new to Perl (but it 
> seems to be the only possible language given my hosting situation) but 
> relatively experienced otherwise. Thoughts?
> 
> - chrismurf
> 
> ================================
> Can't load '/home/[edit]/perl/5.6.1/auto/RDF/Redland/CORE.so' for module 
> RDF::Redland::CORE: librdf.so.0: cannot open shared object file: No such 
> file or directory at /usr/lib/perl/5.6.1/DynaLoader.pm line 202.
> at /home/[edit]/perl/5.6.1/RDF/Redland/CORE.pm line 7
> Compilation failed in require at /home/[edit]/lib/perl/5.6.1/RDF/Redland.pm 
> line 39.


Dave