{
    "mode": "man",
    "parameter": "perl5241delta",
    "section": "1",
    "url": "https://www.chedong.com/phpMan.php/man/perl5241delta/1/json",
    "generated": "2026-06-12T04:51:19Z",
    "sections": {
        "NAME": {
            "content": "perl5241delta - what is new for perl v5.24.1\n",
            "subsections": []
        },
        "DESCRIPTION": {
            "content": "This document describes differences between the 5.24.0 release and the 5.24.1 release.\n\nIf you are upgrading from an earlier release such as 5.22.0, first read perl5240delta, which\ndescribes differences between 5.22.0 and 5.24.0.\n",
            "subsections": []
        },
        "Security": {
            "content": "",
            "subsections": [
                {
                    "name": "-Di switch is now required for PerlIO debugging output",
                    "content": "Previously PerlIO debugging output would be sent to the file specified by the \"PERLIODEBUG\"\nenvironment variable if perl wasn't running setuid and the -T or -t switches hadn't been\nparsed yet.\n\nIf perl performed output at a point where it hadn't yet parsed its switches this could result\nin perl creating or overwriting the file named by \"PERLIODEBUG\" even when the -T switch had\nbeen supplied.\n\nPerl now requires the -Di switch to produce PerlIO debugging output.  By default this is\nwritten to \"stderr\", but can optionally be redirected to a file by setting the \"PERLIODEBUG\"\nenvironment variable.\n\nIf perl is running setuid or the -T switch was supplied \"PERLIODEBUG\" is ignored and the\ndebugging output is sent to \"stderr\" as for any other -D switch.\n\nCore modules and tools no longer search \".\" for optional modules\nThe tools and many modules supplied in core no longer search the default current directory\nentry in @INC for optional modules.  For example, Storable will remove the final \".\" from\n@INC before trying to load Log::Agent.\n\nThis prevents an attacker injecting an optional module into a process run by another user\nwhere the current directory is writable by the attacker, e.g. the /tmp directory.\n\nIn most cases this removal should not cause problems, but difficulties were encountered with\nbase, which treats every module name supplied as optional.  These difficulties have not yet\nbeen resolved, so for this release there are no changes to base.  We hope to have a fix for\nbase in Perl 5.24.2.\n\nTo protect your own code from this attack, either remove the default \".\"  entry from @INC at\nthe start of your script, so:\n\n#!/usr/bin/perl\nuse strict;\n...\n\nbecomes:\n\n#!/usr/bin/perl\nBEGIN { pop @INC if $INC[-1] eq '.' }\nuse strict;\n...\n\nor for modules, remove \".\" from a localized @INC, so:\n\nmy $canfoo = eval { require Foo; }\n\nbecomes:\n\nmy $canfoo = eval {\nlocal @INC = @INC;\npop @INC if $INC[-1] eq '.';\nrequire Foo;\n};\n"
                },
                {
                    "name": "Incompatible Changes",
                    "content": "Other than the security changes above there are no changes intentionally incompatible with\nPerl 5.24.0.  If any exist, they are bugs, and we request that you submit a report.  See\n\"Reporting Bugs\" below.\n"
                },
                {
                    "name": "Modules and Pragmata",
                    "content": ""
                },
                {
                    "name": "Updated Modules and Pragmata",
                    "content": "•   Archive::Tar has been upgraded from version 2.04 to 2.0401.\n\n•   bignum has been upgraded from version 0.42 to 0.4201.\n\n•   CPAN has been upgraded from version 2.11 to 2.1101.\n\n•   Digest has been upgraded from version 1.17 to 1.1701.\n\n•   Digest::SHA has been upgraded from version 5.95 to 5.9501.\n\n•   Encode has been upgraded from version 2.80 to 2.8001.\n\n•   ExtUtils::MakeMaker has been upgraded from version 7.1001 to 7.1002.\n\n•   File::Fetch has been upgraded from version 0.48 to 0.4801.\n\n•   File::Spec has been upgraded from version 3.63 to 3.6301.\n\n•   HTTP::Tiny has been upgraded from version 0.056 to 0.056001.\n\n•   IO has been upgraded from version 1.36 to 1.3601.\n\n•   The IO-Compress modules have been upgraded from version 2.069 to 2.069001.\n\n•   IPC::Cmd has been upgraded from version 0.92 to 0.9201.\n\n•   JSON::PP has been upgraded from version 2.27300 to 2.2730001.\n\n•   Locale::Maketext has been upgraded from version 1.26 to 1.2601.\n\n•   Locale::Maketext::Simple has been upgraded from version 0.21 to 0.2101.\n\n•   Memoize has been upgraded from version 1.03 to 1.0301.\n\n•   Module::CoreList has been upgraded from version 5.20160506 to 5.2017011424.\n\n•   Net::Ping has been upgraded from version 2.43 to 2.4301.\n\n•   Parse::CPAN::Meta has been upgraded from version 1.4417 to 1.4417001.\n\n•   Pod::Html has been upgraded from version 1.22 to 1.2201.\n\n•   Pod::Perldoc has been upgraded from version 3.2502 to 3.2503.\n\n•   Storable has been upgraded from version 2.56 to 2.5601.\n\n•   Sys::Syslog has been upgraded from version 0.33 to 0.3301.\n\n•   Test has been upgraded from version 1.28 to 1.2801.\n\n•   Test::Harness has been upgraded from version 3.36 to 3.3601.\n\n•   XSLoader has been upgraded from version 0.21 to 0.22, fixing a security hole in which\nbinary files could be loaded from a path outside of @INC.  [GH #15418]\n<https://github.com/Perl/perl5/issues/15418>\n"
                }
            ]
        },
        "Documentation": {
            "content": "",
            "subsections": [
                {
                    "name": "Changes to Existing Documentation",
                    "content": "perlapio\n\n•   The documentation of \"PERLIODEBUG\" has been updated.\n\nperlrun\n\n•   The new -Di switch has been documented, and the documentation of \"PERLIODEBUG\" has been\nupdated.\n"
                }
            ]
        },
        "Testing": {
            "content": "•   A new test script, t/run/switchDx.t, has been added to test that the new -Di switch is\nworking correctly.\n",
            "subsections": [
                {
                    "name": "Selected Bug Fixes",
                    "content": "•   The change to hashbang redirection introduced in Perl 5.24.0, whereby perl would redirect\nto another interpreter (Perl 6) if it found a hashbang path which contains \"perl\"\nfollowed by \"6\", has been reverted because it broke in cases such as\n\"#!/opt/perl64/bin/perl\".\n"
                }
            ]
        },
        "Acknowledgements": {
            "content": "Perl 5.24.1 represents approximately 8 months of development since Perl 5.24.0 and contains\napproximately 8,100 lines of changes across 240 files from 18 authors.\n\nExcluding auto-generated files, documentation and release tools, there were approximately\n2,200 lines of changes to 170 .pm, .t, .c and .h files.\n\nPerl continues to flourish into its third decade thanks to a vibrant community of users and\ndevelopers.  The following people are known to have contributed the improvements that became\nPerl 5.24.1:\n\nAaron Crane, Alex Vandiver, Aristotle Pagaltzis, Chad Granum, Chris 'BinGOs' Williams, Craig\nA. Berry, Father Chrysostomos, James E Keenan, Jarkko Hietaniemi, Karen Etheridge, Leon\nTimmermans, Matthew Horsfall, Ricardo Signes, Sawyer X, Sébastien Aperghis-Tramoni, Stevan\nLittle, Steve Hay, Tony Cook.\n\nThe list above is almost certainly incomplete as it is automatically generated from version\ncontrol history.  In particular, it does not include the names of the (very much appreciated)\ncontributors who reported issues to the Perl bug tracker.\n\nMany of the changes included in this version originated in the CPAN modules included in\nPerl's core.  We're grateful to the entire CPAN community for helping Perl to flourish.\n\nFor a more complete list of all of Perl's historical contributors, please see the AUTHORS\nfile in the Perl source distribution.\n",
            "subsections": [
                {
                    "name": "Reporting Bugs",
                    "content": "If you find what you think is a bug, you might check the articles recently posted to the\ncomp.lang.perl.misc newsgroup and the Perl bug database at <https://rt.perl.org/> .  There\nmay also be information at <http://www.perl.org/> , the Perl Home Page.\n\nIf you believe you have an unreported bug, please run the perlbug program included with your\nrelease.  Be sure to trim your bug down to a tiny but sufficient test case.  Your bug report,\nalong with the output of \"perl -V\", will be sent off to perlbug@perl.org to be analysed by\nthe Perl porting team.\n\nIf the bug you are reporting has security implications which make it inappropriate to send to\na publicly archived mailing list, then see \"SECURITY VULNERABILITY CONTACT INFORMATION\" in\nperlsec for details of how to report the issue.\n"
                }
            ]
        },
        "SEE ALSO": {
            "content": "The Changes file for an explanation of how to view exhaustive details on what changed.\n\nThe INSTALL file for how to build Perl.\n\nThe README file for general stuff.\n\nThe Artistic and Copying files for copyright information.\n\n\n\nperl v5.34.0                                 2025-07-25                             PERL5241DELTA(1)",
            "subsections": []
        }
    },
    "summary": "perl5241delta - what is new for perl v5.24.1",
    "flags": [],
    "examples": [],
    "see_also": [],
    "tldr": {
        "source": "not_found",
        "examples": []
    }
}