Clarify C<crypt> documentation

[p5sagit/p5-mst-13.2.git] / pod / perlrun.pod

diff --git a/pod/perlrun.pod b/pod/perlrun.pod
index df606bf..f90e642 100644 (file)
--- a/pod/perlrun.pod
+++ b/pod/perlrun.pod
@@ -439,5 +439,73 @@ terminated with C<__END__> if there is trailing garbage to be ignored (the
 script can process any or all of the trailing garbage via the DATA
 filehandle if desired).
 
+=back
+
+=head1 ENVIRONMENT
+
+=over 12
+
+=item HOME
+
+Used if chdir has no argument.
+
+=item LOGDIR
+
+Used if chdir has no argument and HOME is not set.
+
+=item PATH
+
+Used in executing subprocesses, and in finding the script if B<-S> is
+used.
+
+=item PERL5LIB
+
+A colon-separated list of directories in which to look for Perl library
+files before looking in the standard library and the current
+directory.  If PERL5LIB is not defined, PERLLIB is used.  When running
+taint checks (because the script was running setuid or setgid, or the
+B<-T> switch was used), neither variable is used.  The script should
+instead say
+
+    use lib "/my/directory";
+
+=item PERLLIB
+
+A colon-separated list of directories in which to look for Perl library
+files before looking in the standard library and the current directory.
+If PERL5LIB is defined, PERLLIB is not used.
+
+=item PERL5DB
+
+The command used to load the debugger code.  The default is:
+
+       BEGIN { require 'perl5db.pl' }
+
+=item PERL_DEBUG_MSTATS
+
+Relevant only if your perl executable was built with B<-DDEBUGGING_MSTATS>,
+if set, this causes memory statistics to be dumped after execution.  If set
+to an integer greater than one, also causes memory statistics to be dumped
+after compilation.
+
+=item PERL_DESTRUCT_LEVEL
+
+Relevant only if your perl executable was built with B<-DDEBUGGING>,
+this controls the behavior of global destruction of objects and other
+references.
 
 =back
+
+Perl also has environment variables that control how Perl handles data
+specific to particular natural languages.  See L<perllocale>.
+
+Apart from these, Perl uses no other environment variables, except
+to make them available to the script being executed, and to child
+processes.  However, scripts running setuid would do well to execute
+the following lines before doing anything else, just to keep people
+honest:
+
+    $ENV{'PATH'} = '/bin:/usr/bin';    # or whatever you need
+    $ENV{'SHELL'} = '/bin/sh' if defined $ENV{'SHELL'};
+    $ENV{'IFS'} = ''          if defined $ENV{'IFS'};
+