opendir(), closedir(), seekdir(), rewinddir(), glob(); symlink(),
readlink().
+See also L</"Virtualize operating system access">.
+
=head2 -C on the #! line
It should be possible to make -C work correctly if found on the #! line,
implementation, the approaches could be merged.
What would this give us? One often-asked-for feature this would
-enable is using Unicode for filenames (and other "names" like %ENV,
-usernames, hostnames, and so forth.) But this would also allow for
-things like virtual filesystems, virtual networks, and "sandboxes"
-(though as long as dynamic loading of random object code is allowed,
-not very safe sandboxes since external code of course know not of
-Perl's vtables). An example of a smaller "sandbox" is that this
-feature can be used to implement per-thread working directories:
-Win32 already does this.
+enable is using Unicode for filenames, and other "names" like %ENV,
+usernames, hostnames, and so forth.
+(See L<perlunicode/"When Unicode Does Not Happen">.)
+
+But this kind of virtualization would also allow for things like
+virtual filesystems, virtual networks, and "sandboxes" (though as long
+as dynamic loading of random object code is allowed, not very safe
+sandboxes since external code of course know not of Perl's vtables).
+An example of a smaller "sandbox" is that this feature can be used to
+implement per-thread working directories: Win32 already does this.
+
+See also L</"Extend PerlIO and PerlIO::Scalar">.
=head1 Big projects