World writable Permission Needed or Not

21/02/2008 - 10:43 von Debu | Report spam
Hi,

Let me explain the exact problem. I have connected two boxes
running SVR4 Unix through serial ports via a NULL modem cable. Two
ordinary/Normal users are siting on both end using "/dev/console" not
any Pseudo terminals. I can communicate in between them using "/usr/
bin/cu -l /dev/term/01" which works via "/usr/sbin/cs" daemon.

One interesting thing here is after connection establishment i can
write on both end; even if i remove world writable from "/dev/term/
01". How this thing is possible if no write permission is there on the
serial device????????

wheather i need world writable for serial devices or not if i will
connect to some modem through serial communication??????
 

Lesen sie die antworten

#1 Hauke Laging
21/02/2008 - 11:27 | Warnen spam
Debu schrieb am Donnerstag 21 Februar 2008 10:43:

running SVR4 Unix



You post an English message into a German Linux (only) group.
Anything wrong with that?


One interesting thing here is after connection establishment i can
write on both end; even if i remove world writable from "/dev/term/
01". How this thing is possible if no write permission is there on
the serial device????????



More "?" don't make the question better. The kernel checks
permissions only at the moment of opening the file handle.
Afterwards you can even delete the file - and it keeps accessible
for the process which opened it before.


Hauke
http://www.hauke-laging.de/ideen/
http://www.hauke-laging.de/software/
http://zeitstempel-signatur.hauke-laging.de/
Wie können 59.054.087 Leute nur so dumm sein?

Ähnliche fragen