On Wed, Jul 07, 2010 at 02:24:45PM -0700, Steven Dake wrote: > Not sure how to map a readdir to readdir_r on a thread unsafe system... > perhaps with thread keys. In any regard, seems pointless, readdir_r is > there and what POSIX specifies for this purpose.
Override opendir and allocate the buffer then and return a pointer to it through a custom 'DIR *'. >> FWIW, I've always considered readdir_r to be broken, you pass in a >> buffer without passing in a size and hope everything works out. Your > > I also have objections to some POSIX standard APIs - however, using > non-reentrant POSIX apis when reentrant POSIX APIs are available seems > counterproductive. Well, if the non-reentrant ones are badly designed I'm not sure it is a good trade.. Ie Solaris's man pages say: It is safe to use readdir() in a threaded application, so long as only one thread reads from the directory stream at any given time. The readdir() function is generally preferred over the readdir_r() function. Also see http://lists.grok.org.uk/pipermail/full-disclosure/2005-November/038295.html The horribleness of readdir_r is well documented, and is partly why libc's advocate thread safe readdir() desipte the existence of readdir_r. >> proposed patch to libibverbs is also not-portable because it uses >> NAME_MAX, not pathconf.. Sigh POSIX. > On bsd/solaris/darwin/linux, NAME_MAX is defined. Not sure which other > POSIX systems one would care about.. If all you care able is bsd/solaris/darwin/linux then this is a non-problem, AFAIK they have sane libc's :) Ie I just checked and openbsd libc has been using a dynamic buffer allocated at opendir since 1996. If you care about theortical portability then you have to worry about NAME_MAX too.. Jason -- To unsubscribe from this list: send the line "unsubscribe linux-rdma" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
