README.freebsd - Perl version 5 on FreeBSD systems


This document describes various features of FreeBSD that will affect how Perl version 5 (hereafter just Perl) is compiled and/or runs.

FreeBSD core dumps from readdir_r with ithreads

When perl is configured to use ithreads, it will use re-entrant library calls in preference to non-re-entrant versions. There is a bug in FreeBSD's readdir_r function in versions 4.5 and earlier that can cause a SEGV when reading large directories. A patch for FreeBSD libc is available (see ) which has been integrated into FreeBSD 4.6.

$^X doesn't always contain a full path in FreeBSD

perl 5.8.0 sets $^X where possible to a full path by asking the operating system. On FreeBSD the full path of the perl interpreter is found by reading the symlink /proc/curproc/file. There is a bug on FreeBSD, where the result of reading this symlink is can be wrong in certain circumstances (see ). In these cases perl will fall back to the old behaviour of using C's argv[0] value for $^X.

Perl will no longer be part of ``base FreeBSD''

Not as bad as it sounds--what this means is that Perl will no longer be part of the kernel build system of FreeBSD. Perl will still very probably be part of the ``default install'', and in any case the latest version will be in the ports system. The first FreeBSD version this change will affect is 5.0, all 4.n versions will keep the status quo.


Nicholas Clark <>, collating wisdom supplied by Slaven Rezic and Tim Bunce.

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