If the only systems running Perl were Unix, Dos, or Mac this would be easy: all I would need to do is canonize the two paths and then compare them as strings.
Considering that Unix allows symbolic links, and mounts anywhere on the current filesystem (not to mention the fact that things can be mounted more than once), this is not as easy as you may think.
For example, if A is a substring of B, then A is the parent of B.
Yes, but the reverse isn't true. If A isn't a substring of B, then that doesn't mean A isn't the parent of B.

In reply to Re: How does compare the relationship between two file system paths in a portable way? by JavaFan
in thread How does one compare the relationship between two file system paths in a portable way? by ELISHEVA

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":



  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.