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Timeline for Why does '/' have an '..' entry?

Current License: CC BY-SA 3.0

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Feb 2, 2014 at 10:39 comment added dotancohen @WarrenYoung: I would change "reasonable" to "reasonable and unambiguous".
Jan 23, 2013 at 23:39 comment added Warren Young As I wrote in my answer, it makes the system consistent. There is no special case. Also, as a rule, Unix doesn't second-guess the user. If there is a reasonable way for the system to comply with a command, it will. The alternative is a system that's always telling you "no," or asking "are you really really sure?"
Jan 22, 2013 at 12:27 comment added amyassin @WarrenYoung what could be a good use for that feature??
Dec 3, 2012 at 3:50 comment added Warren Young @musiphil: It's a good thing. Michael was just pointing out that it's a feature that can be exploited for bad ends, if code isn't written to cope with the exploit. If we got rid of all features that can be exploited, computers would be very dull things.
Dec 3, 2012 at 3:10 comment added musiphil @MichaelMrozek: I'm confused whether it's a good thing or a bad thing that / has .. that points to itself...
Oct 11, 2011 at 8:16 review Suggested edits
Oct 11, 2011 at 11:02
May 2, 2011 at 22:42 history edited Warren Young CC BY-SA 3.0
clarified the significance of both inode values being the same
Jan 16, 2011 at 23:46 vote accept Nathan Osman
Jan 12, 2011 at 14:37 comment added jlliagre I see, they should at least use canonicalize_file_name or realpath.
Jan 12, 2011 at 8:08 comment added Gilles 'SO- stop being evil' @jlliagre: There are programs that check whether a file is under the current directory by testing whether it begins with /. Between ../ (not necessarily at the beginning!) and symbolic links, it's very hard to do, especially considering the attacker may be moving directories under the program's nose.
Jan 12, 2011 at 7:46 comment added jlliagre What difference would that make with simply using /etc/passwd ?
Jan 12, 2011 at 3:36 comment added Michael Mrozek @George I believe exploits that take advantage of relative paths use that; you don't have to guess the current folder, you just do ../../../../../../../../../../../../../../../../etc/passwd
Jan 12, 2011 at 3:09 comment added Nathan Osman So /../../../../.. is a valid path then? (And is equal to /.)
Jan 12, 2011 at 2:28 history answered Warren Young CC BY-SA 2.5