Issue could be considered as continuation of [9e6b569963]...

Under windows it is possible to have relative paths (file and directory names) starting with tilde, as such it is "partially absolute" path, so in my opinion should be interpreted as relative if used in file join.<br/>
From this point of view <code>file join $dirname $filename</code> behaves incorrectly under windows if <code>filename</code> starting with <code>~</code> characters:

<code><pre style="padding-left:10pt">
% file join $env(tmp) ~*
~*
% file join $env(tmp) ~abc.txt
~abc.txt


Where <code>glob</code> already has correct behavior here:
<code><pre style="padding-left:10pt">
% glob -directory e:/temp ~*

% glob

% cd e:/temp
% glob [pwd]/~*


Just this one is a bit confusing (I know it is a bit "ambiguous", but...):
<code><pre style="padding-left:10pt">
% glob ~*
user "*" doesn't exist

Despite ambiguity it looks still weird to me:

<ol>
<li> either the decision remains "path of pattern is absolute", it could be fixed to list all users/homes where caller is permitted.</li>
<li> or the decision going either to "path of pattern considered as relative" under windows, it should behave like <code>glob (so find all files starting with "~" in current directory).</li>
</ol>

Anyway (after fix) it could be additionally documented (with difference between unix/windows).