On Tue, Jun 25, 2013 at 11:34:03PM +0200, Armin Rigo wrote: > Sorry, I don't follow you. As far as I know the Linux man page is not > clear about what occurs to errno if readdir() doesn't return NULL...
Exactly :) My reading of it is that readdir returns: NULL and sets errno if an error occurred; NULL and doesn't change errno if end of directory was reached; non-NULL and no guarantees about errno if it's half-way through reading a directory and no errors occurred. I came to the conclusion that I had to be defensive and do the following: errno must be set to 0 before readdir; only if NULL is returned can errno be checked to see its value. [When I read through the OpenBSD source, the implementation happens to define that if non-NULL is returned, errno isn't fiddled about with (unless getdirentries is buggy, which I didn't check!). The documentation does not mention anything about this, so I think one has to assume that all bets are off, particularly on other OS's.] This all seems a big mess to me, but since I changed my code, I've had no problems with readdir (on OpenBSD or Linux), so I assume my defensive action was successful... Laurie -- Personal http://tratt.net/laurie/ Software Development Team http://soft-dev.org/ https://github.com/ltratt http://twitter.com/laurencetratt _______________________________________________ pypy-dev mailing list pypy-dev@python.org http://mail.python.org/mailman/listinfo/pypy-dev
