-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 According to Olivier Delhomme on 3/8/2006 12:45 PM: > Le Mon, 06 Mar 2006 18:20:12 -0500, Phillip Susi disait : > >> I'm confused. You can't open() and write() to a directory, so how does >> it make any sense to ask dd to set O_DIRECTORY? > > So do I ...I never used open() with a directory, but why shouldn't it > be possible ?
It's possible to open directories read-only, but then you can't read() that file descriptor. Beyond atomic existance checks, about all that can be usefully done with a directory fd is using fdopendir() on it (as a replacement to opendir, especially useful when using openat() and friends). But I still think Paul's patch was worthwhile, from the completeness point of view - dd now supports every O_* flag possible, even if there is not much use for it. > > I looked to the man 2 open page and I saw the following which confuses > me more : > > O_DIRECTORY > If pathname is not a directory, cause the open to > fail. This flag is Linux-specific, and was added in kernel version > 2.1.126, to avoid denial-of- service problems if opendir(3) is called > on a FIFO or tape device, but should not be used outside of the > implementation of opendir. > > > So if this flag is linux specific does it mean that dd iflag=directory > won't run on other unices ? The dd code is conditionally compiled so that platforms not supporting the various O_* flags do not accept that particular flag, nor document it in the --help output. Just as you can't use dd iflag=directory on Solaris, you can't use dd iflag=nolinks on Linux. - -- Life is short - so eat dessert first! Eric Blake [EMAIL PROTECTED] -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.2.1 (Cygwin) Comment: Public key at home.comcast.net/~ericblake/eblake.gpg Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org iD8DBQFEINGr84KuGfSFAYARAkLPAJ96BqO/5D5Rw1I+jpb0rHjxCye/0wCgmYif 2QJGGeJsO4C7xXRLVVc3uZk= =J0WG -----END PGP SIGNATURE----- _______________________________________________ Bug-coreutils mailing list Bug-coreutils@gnu.org http://lists.gnu.org/mailman/listinfo/bug-coreutils
