Messages in this thread | | | Date | Mon, 10 Jul 2006 21:07:46 -0400 | From | "Albert Cahalan" <> | Subject | Re: Opinions on removing /proc/tty? |
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On 7/10/06, Jan Engelhardt <jengelh@linux01.gwdg.de> wrote: > >> > Just do /proc/*/tty links and all will be good. This even > >> > handles the case of two different names for the same dev_t. > >> > > >> Is this for the controlling tty? Then it should be ctty. > > > > Eeeew, an extra byte so it can look ugly. > > What other special tty is there? > > > Any fd, for that matter. > > 00:09 shanghai:/dev/shm > ls -l /proc/$$/fd > total 4 > dr-x------ 2 jengelh users 0 Jul 11 00:16 . > dr-xr-xr-x 5 jengelh root 0 Jul 11 00:04 .. > lrwx------ 1 jengelh users 64 Jul 11 00:16 0 -> /dev/pts/2 > lrwx------ 1 jengelh users 64 Jul 11 00:16 1 -> /dev/pts/2 > lrwx------ 1 jengelh users 64 Jul 11 00:16 2 -> /dev/pts/2 > lrwx------ 1 jengelh users 64 Jul 11 00:16 255 -> /dev/pts/2 > and CTTY is /dev/tty1. > > So what would /proc/$$/tty - ambiguous name - point to, the normal (attached) > or the ctty? Not to mention exotic, yet possible things
The tty is obviously one and the same as:
a. "tty" in the kernel's struct signal_struct b. the "TTY" or "TT" reported by ps. c. what "/dev/tty" refers to
Any other tty is not "the tty". Exactly one tty is special.
On any of Linux, MacOS, Solaris, NetBSD, OpenBSD:
$ ls /dev/tty /dev/ctty ls: /dev/ctty: No such file or directory /dev/tty
Lord only knows why FreeBSD has both. Unlike Linux, they don't supply a man page. On a Linux system, "man 4 tty" is useful. On a Solaris system, "man -s 7d tty" is useful. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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