title: Private perlbrew and CPAN not working. Still. Again
body: <p>I thought I had it working.</p>
  
  <p>I have an entirely private version of Perl 5.16 (by private I mean local to my home directory), and a private place for CPAN modules.  I followed the instructions at <a href="http://blog.fox.geek.nz/2010/09/installing-multiple-perls-with.html" rel="nofollow">http://blog.fox.geek.nz/2010/09/installing-multiple-perls-with.html</a> (adjusting for its slight out-of-datedness), which claims to entirely sidestep the need for local::lib.  I used the cpanm that the above-mentioned instrux installed, to install Cache::Memcached::Fast.pm, and successfully ran a Perl program that used this module.</p>
  
  <p>Today it's not working.</p>
  
  <pre><code>Can't locate Cache/Memcached/Fast.pm in @INC (@INC contains:     
  /Users/chap/perl5/perlbrew/perls/perl-5.16.1/lib/site_perl/5.16.1/darwin-2level
  /Users/chap/perl5/perlbrew/perls/perl-5.16.1/lib/site_perl/5.16.
  /Users/chap/perl5/perlbrew/perls/perl-5.16.1/lib/5.16.1/darwin-2level
  /Users/chap/perl5/perlbrew/perls/perl-5.16.1/lib/5.16.1 .) at ./memget line 11.
  </code></pre>
  
  <p>Some troubleshooting:</p>
  
  <pre><code>/Users/chap$ perlbrew use
  Currently using perl-5.16.1
  </code></pre>
  
  <p>...sweet.</p>
  
  <pre><code>/Users/chap$ which perl
  /Users/chap/perl5/perlbrew/perls/perl-5.16.1/bin/perl
  </code></pre>
  
  <p>...awesome.</p>
  
  <pre><code>/Users/chap$ perlbrew switch perl-5.16.1
  /Users/chap$ cpanm --interactive -v App::cpanoutdated
  cpanm (App::cpanminus) 1.5014 on perl 5.012004 built for darwin-thread-multi-2level
  Work directory is /Users/chap/.cpanm/work/1350175791.76873
  You have make /usr/bin/make
  You have LWP 6.03
  You have /usr/bin/tar: bsdtar 2.8.3 - libarchive 2.8.3
  You have /usr/bin/unzip
  Searching App::cpanoutdated on cpanmetadb ...
  !
  ! Can't write to /Library/Perl/5.12 and /usr/local/bin: Installing modules to /Users/chap/perl5
  ! To turn off this warning, you have to do one of the following:
  !   - run me as a root or with --sudo option (to install to /Library/Perl/5.12 and /usr/local/bin)
  !   - Configure local::lib your existing local::lib in this shell to set PERL_MM_OPT etc.
  !   - Install local::lib by running the following commands
  !
  !         cpanm --local-lib=~/perl5 local::lib &amp;&amp; eval $(perl -I ~/perl5/lib/perl5/ -Mlocal::lib)
  !
  Checking if you have ExtUtils::MakeMaker 6.31 ... Yes (6.62)
  Checking if you have ExtUtils::Install 1.46 ... Yes (1.55)
  App::cpanoutdated is up to date. (0.23)
  </code></pre>
  
  <p>Uh oh.  Why the system Perl???</p>