Hi Harald,

> As far as I know is tty specified to test the stdin so fd 0 is the
> right one (fd 2 was a typo of mine, sorry). Currently Busybox and GNU
> tty test stdin and glibc does readlink /proc/self/fd/0 (from strace
> output).

 Oh, right, my bad. /proc/self/fd/0, then: glibc is doing the right
thing. (For once.)
 However, note that /proc/self/fd is Linux-only, whereas /dev/pts
is Unix98, so supposedly more portable. I agree that the uClibc
should optimize the Linux case into readlink'ing /proc/self/fd/0,
though.


>> but I'm fairly sure you will break numerous other applications
>> by dropping the read permissions on /dev/pts/.
> 
> Currently none!

 Fine - but Rich Felker writes (on the uClibc mailing-list):

<< Please note that this does not provide *ANY* privacy/security
<< advantage. If you want a list of open ptys and owners, you can just
<< try stat() on /dev/pts/%d for each integer and get the same
<< information you would have gotten from reading the directory. To make
<< this secure, the kernel would need to be changed to generate random
<< tokens of at least 64bit for each pty...

 And he's right: no use preventing a directory from being read if the
names of the files it contains are so easily predictable.

 I'm not going to play postman between you and [email protected] for
the whole thread. If you want to answer, please subscribe to the uClibc
mailing-list. ;)

-- 
 Laurent
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