In many file systems, ".." corresponds to the parent directory. How does this happen with urls? I have seen several examples that behave according to this pattern, but is this a standard (RFC)? A.
Of course, this is the standard http://www.w3.org/Addressing/rfc1808.txt describes it, segment/.. is iteratively deleted from left to right.
segment/..
The exact same thing.
http://www.mysite.com/dir1/dir2/dir3/index.html
the link to "../../me.jpg" should give you http://www.mysite.com/dir1/me.jpg
The red cod virus that went back many years ago attacked IIS sites because c: \ inetpub .. was the root document, and if you made a URL like /../../../../windows/ cmd.exe% 20dir it will execute it!