In perl.git, the branch blead has been updated <http://perl5.git.perl.org/perl.git/commitdiff/064fb7979931c2a2ac6711c9687db30bd89dcde8?hp=610996fda2dae66f57562c2ae9ab5c005b8e0c69>
- Log ----------------------------------------------------------------- commit 064fb7979931c2a2ac6711c9687db30bd89dcde8 Author: Leon Timmermans <faw...@gmail.com> Date: Wed May 15 23:04:03 2013 +0200 Clarified perldelta entry for UID/GID magic variables ----------------------------------------------------------------------- Summary of changes: pod/perldelta.pod | 17 +++++++++++++++-- 1 files changed, 15 insertions(+), 2 deletions(-) diff --git a/pod/perldelta.pod b/pod/perldelta.pod index 2721a1c..4a21c4a 100644 --- a/pod/perldelta.pod +++ b/pod/perldelta.pod @@ -763,8 +763,21 @@ active user. Swapping of $< and $> -For more information about this future deprecation, see L<the relevant RT -ticket|https://rt.perl.org/rt3/Ticket/Display.html?id=96212>. +Perl has supported the idiom of swapping $< and $> (and likewise $( and +$)) to temporarily drop permissions since 5.0, like this: + + ($<, $>) = ($>, $<); + +However, this idiom modifies the real user/group id, which can have +undesirable side-effects, is no longer useful on any platform perl +supports and complicates the implementation of these variables and list +assignment in general. + +As an alternative, assignment only to C<< $> >> is recommended: + + local $> = $<; + +See also: L<Setuid Demystified|http://www.cs.berkeley.edu/~daw/papers/setuid-usenix02.pdf>. =item * -- Perl5 Master Repository