in reply to Re: What is cpan (the installer) doing prepending all these directories to the PERL5LIB path?
in thread What is cpan (the installer) doing prepending all these directories to the PERL5LIB path?

He's not saying anything like that. When he's doing an install it is letting him know it is adding other builds to PERL5LIB for that install, and the number is increasing, not that that env var is somehow persisting.
  • Comment on Re^2: What is cpan (the installer) doing prepending all these directories to the PERL5LIB path?

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Re^3: What is cpan (the installer) doing prepending all these directories to the PERL5LIB path?
by Intrepid (Curate) on Nov 14, 2025 at 19:46 UTC

    That's right, ysth. I do understand how env works for the currently-running process, its child processes, its parent process, and so on, ikegami.

    Unrelated to the reported behavior is a spurious error message I'm seeing:

    prerequisite moduleFile::Basename not known
    

    This message also started appearing rather recently and doesn't seem to be connected to any actual failure in cpan. I thought I'd mention it here since it's a "while we're discussing cpan" kind of thing.

        — Soren

    Nov 14, 2025 at 19:44 UTC

    A just machine to make big decisions
    Programmed by fellows (and gals) with compassion and vision
    We'll be clean when their work is done
    We'll be eternally free yes, and eternally young
    Donald Fagen —> I.G.Y.
    (Slightly modified for inclusiveness)

      So what do you claim is sticking around?

        It should be clearer if I provide some context. The lines in bold below are directly or possibly relevant to the reported behavior. HTH.

        $ perl -MCPAN -e shell
        cpan1> install XML::RSS
        CPAN: Term::ANSIColor loaded ok (v5.01)
        CPAN: HTTP::Tiny loaded ok (v0.090)
        CPAN: Net::SSLeay loaded ok (v1.94)
        CPAN: IO::Socket::SSL loaded ok (v2.095)
        Fetching with HTTP::Tiny:
        https://cpan.org/authors/01mailrc.txt.gz
        CPAN: CPAN::SQLite loaded ok (v0.220)
        Fetching with HTTP::Tiny:
        https://cpan.org/modules/02packages.details.txt.gz
        Fetching with HTTP::Tiny:
        https://cpan.org/modules/03modlist.data.gz
        CPAN: YAML::XS loaded ok (vv0.902.0)
        Reading 109 yaml files from /cygdrive/C/Users/somia/cygwin-perl-cpan/build/
        ............................................................................DONE
        Restored the state of 19 (in 1.4501 secs)
        Database was generated on Sun, 16 Nov 2025 19:26:16 GMT
        Updating database file ... Done!
        Running install for module 'XML::RSS'
        CPAN: CPAN::Kwalify loaded ok (v5.50)
        Prepending blib/arch and blib/lib of 19 build dirs to PERL5LIB, reaching size 2952; for 'get'
        Fetching with HTTP::Tiny:
        https://cpan.org/authors/id/S/SH/SHLOMIF/XML-RSS-1.65.tar.gz
        CPAN: Digest::SHA loaded ok (v6.04)
        CPAN: Compress::Zlib loaded ok (v2.213)
        Checksum for C:/Users/somia/AppData/strawberry-perl-sourcecache/authors/id/S/SH/SHLOMIF/XML-RSS-1.65.tar.gz ok
        CPAN: Archive::Tar loaded ok (v3.04)
        XML-RSS-1.65
        XML-RSS-1.65/TODO
        XML-RSS-1.65/README
        XML-RSS-1.65/Changes
        
        ...
        
        Result: PASS
        (C:/ix/cygwin/bin/make test exited with 0)
        CPAN::Reporter: Test result is 'pass', All tests successful.
        CPAN::Reporter: preparing a CPAN Testers report for XML-RSS-1.65
        Do you want to send the report? (yes/no) yes
        CPAN::Reporter: sending test report with 'pass' via Metabase
          SHLOMIF/XML-RSS-1.65.tar.gz
          C:/ix/cygwin/bin/make test -- OK
        Running make install for SHLOMIF/XML-RSS-1.65.tar.gz
        Prepending blib/arch and blib/lib of 20 build dirs to PERL5LIB, reaching size 3095; for 'install'
        
        ...
        

            — Soren


        Nov 18, 2025 at 23:07 UTC