perlfreebsd - Perl version 5 on FreeBSD systems

       Nicholas Clark <nick@ccl4.org>, collating wisdom supplied by Slaven Rezic and Tim Bunce.

       Please report any errors, updates, or suggestions to <https://github.com/Perl/perl5/issues>.

perl v5.40.1                                       2025-07-25                                     PERLFREEBSD(1)

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

   FreeBSDcoredumpsfromreaddir_rwithithreads
       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
       <https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=30631>) which has been integrated into FreeBSD 4.6.

   $^Xdoesn'talwayscontainafullpathinFreeBSD
       perl 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 using "sysctl" with "KERN_PROC_PATHNAME" if that is supported, else by
       reading the symlink /proc/curproc/file. FreeBSD 7 and earlier has a bug where either approach sometimes
       returns an incorrect value (see <https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=35703>).  In these
       cases perl will fall back to the old behaviour of using C's "argv[0]" value for $^X.

       perlfreebsd - Perl version 5 on FreeBSD systems