"use lib" whith architecture and version specific dirs

jeorgen has asked for the wisdom of the Perl Monks concerning the following question:

Dear fellow monks

I'm installing perl modules at a customer's web account, where we do not have root access. So I have created a local perl library, "/home/customer/customers_perl_modules".

I install modules with CPAN configured for the local library, and sometimes with perl Makefile.PL PREFIX =/home/customer/customers_perl_modules

The info on the local libray is stored in the myconfig.pm in the .cpan directory in the user's home directory.

Now, all the modules installed do indeed end up inside the "/home/customer/customers_perl_modules"directory, but often not directly under it, but deeper, in directories named after the version of perl that is used, the processor architecture, under the library "site_perl". There is:

lib/site_perl,
lib/site_perl/5.005/,
lib/site_perl/5.005/i386-linux/
[download]

Now, writing

use lib "/home/customer/customers_perl_modules";
[download]

doesn't work for the below script, I seem to need the two following "use libs" in the script for it to work:


use lib "/home/customer/customers_perl_modules/lib";          
use lib "/home/customer/customers_perl_modules/lib/site_perl/5.005/i38
+6-linux/"; 
use lib "/home/customer/customers_perl_modules/lib/site_perl/5.005/"; 
use XML::Parser;
use Data::DumpXML;
print "Hi\n";
[download]

It seems kind of counter-productive to manually specify the path to each architecture-specific and version-specific directory. I would have thought that this would be handled automatically either by perl itself or by the lib pragma.

So should I:

a) Use some other way than PREFIX and .cpan/myconfig.pm to tell the modules where to be

b) Manually move the modules up and out of the architecture and version-specific libraries

c) use something else than use lib

d) subclass lib module and auto-create appended paths with version, "site_perl" and architecture values added

e) or is my perl broken

? "perl -V" gives this:

Summary of my perl5 (5.0 patchlevel 5 subversion 3) configuration:
  Platform:
    osname=linux, osvers=2.2.5-22smp, archname=i386-linux
    uname='linux porky.devel.redhat.com 2.2.5-22smp #1 smp wed jun 2 0
+9:11:51 edt 1999 i686 unknown '
    hint=recommended, useposix=true, d_sigaction=define
    usethreads=undef useperlio=undef d_sfio=undef
  Compiler:
    cc='cc', optimize='-O2 -m486 -fno-strength-reduce', gccversion=egc
+s-2.91.66 19990314/Linux (egcs-1.1.2 release)
    cppflags='-Dbool=char -DHAS_BOOL -I/usr/local/include'
    ccflags ='-Dbool=char -DHAS_BOOL -I/usr/local/include'
    stdchar='char', d_stdstdio=undef, usevfork=false
    intsize=4, longsize=4, ptrsize=4, doublesize=8
    d_longlong=define, longlongsize=8, d_longdbl=define, longdblsize=1
+2
    alignbytes=4, usemymalloc=n, prototype=define
  Linker and Libraries:
    ld='cc', ldflags =' -L/usr/local/lib'
    libpth=/usr/local/lib /lib /usr/lib
    libs=-lnsl -ldl -lm -lc -lposix -lcrypt
    libc=, so=so, useshrplib=false, libperl=libperl.a
  Dynamic Linking:
    dlsrc=dl_dlopen.xs, dlext=so, d_dlsymun=undef, ccdlflags='-rdynami
+c'
    cccdlflags='-fpic', lddlflags='-shared -L/usr/local/lib'


Characteristics of this binary (from libperl): 
  Built under linux
  Compiled at Aug 10 2000 15:33:00
  @INC:
    /usr/lib/perl5/5.00503/i386-linux
    /usr/lib/perl5/5.00503
    /usr/lib/perl5/site_perl/5.005/i386-linux
    /usr/lib/perl5/site_perl/5.005
[download]

Am I missing something?

/jeorgen

Comment on "use lib" whith architecture and version specific dirs Select or Download Code

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Re: "use lib" whith architecture and version specific dirs by Fastolfe (Vicar) on Dec 11, 2000 at 07:27 UTC
This is standard behavior (the placing of modules in the directory hierarchy like this). Note your perl -V gives you 4 items in @INC that correspond to equally nested directories with a prefix of /usr/lib/perl5. You're either going to have to recompile Perl to look in this place as well, use multiple 'use lib' statements like you're doing, or combine them all onto one 'use lib' statement: `use lib '/prefix/site_perl', '/prefix/5.00503/', '/prefix/site_perl/5.005/, ...;` [download] The last alternative I'd recommend is to set the PERL5LIB environment variable to include these alternative directories. Set this like you'd set the PATH under unix: a colon-separated list of directories. If you're running under a web server like Apache, you'll have to tell Apache to set these first, or be sure they're set when Apache starts (in its startup script).	[reply] [d/l]
Re: "use lib" whith architecture and version specific dirs by jeorgen (Pilgrim) on Dec 11, 2000 at 07:46 UTC
While re-reading the documentation on use lib and looking through the directory structure again, I realise that all modules have ended up in either `lib/site_perl/5.005/` [download] or in `lib/site_perl/5.005/i386-linux/` [download] ...and according to the documentation on use lib, a: `use lib "customers_perl_modules/lib/site_perl/5.005";` [download] Should be enough, since directly underlying architecture-specific libs should be appended to @INC automagically. ...should be enough. Let me try.. Yep, works! But what happens when perl 5.6 gets installed? /jeorgen	[reply] [d/l] [select]
Re: Re: "use lib" whith architecture and version specific dirs by chipmunk (Parson) on Dec 11, 2000 at 08:29 UTC
The reason for version-specific directories is that a module compiled for one version of perl may not work with another version of perl; this is particularly true of modules with binary pieces. There may also be modules where the newer versions work with 5.6 but not 5.005, so you would install the newer version in site_perl/5.6 while leaving the old version in site_perl/5.005 unchanged. It's possible that none of these conflicts exist for any of the modules you're using, but you can play it safe by reinstalling all the site_perl modules when you upgrade to perl5.6.	[reply]
Re: Re: "use lib" whith architecture and version specific dirs by Fastolfe (Vicar) on Dec 11, 2000 at 08:03 UTC
When Perl 5.6 is installed, it'll need to look in 5.6.0 as well as 5.005 (assuming you let it look in the older place), and you'll need to update your paths to look in the 5.6.0 versions as well.	[reply]
Re: "use lib" whith architecture and version specific dirs by FouRPlaY (Monk) on Dec 12, 2000 at 01:17 UTC
Try: `perl Makefile.PL PREFIX="some/dir" LIB=some/dir"` I had to have both to get my modules to work. FouRPlaY Learning Perl or Going To die() Trying	[reply] [d/l]