Several weeks ago I reported a bug. No answer came, and the bug is still
present in 2.1.127. :-( So I send the report again.
It's possible that an entry remains in the proc fs after the command has
exited. It seems to me that it happens if we run an `ls -l' command in the
/proc/$pid/fd directory while the command runs. After command exits, `ls
/proc' does not write its pid, but /proc/$pid still exists.
See the log file at the end of the message.
Two more questions about /proc/$pid/fd:
1. Instead of 64, could the "correct" length of the symlinks be returned?
2. When a file is deleted, the string "/tmp/x (deleted)" could rather be
"deleted:/tmp/x". This is because it's more similar to the pipe: and
socket: ones, and a normal file _can_ have the name "/tmp/x (deleted)"
so it cannot be told whether this really means a deleted file. On the
other hand, "deleted:/tmp/x" can not be the full name of a real file.
So it would be more simplier and more consequent to parse the
"deleted:/tmp/x" notation within a program.
Bye
Egmont Koblinger
<egmont@math.bme.hu>
Here is the log file how I can invoke the bug:
egmont $ sleep 10 &
[1] 182
egmont $ ls -l /proc/182/fd
total 0
lrwx------ 1 egmont pupil 64 Oct 20 20:50 0 -> /dev/ttyp0
lrwx------ 1 egmont pupil 64 Oct 20 20:50 1 -> /dev/ttyp0
lrwx------ 1 egmont pupil 64 Oct 20 20:50 2 -> /dev/ttyp0
egmont $ ##### wait ten seconds
[1]+ Done sleep 10
egmont $ ls /proc | grep 182
egmont $ ls -l /proc/182
ls: /proc/182/exe: Permission denied
ls: /proc/182/root: Permission denied
ls: /proc/182/cwd: Permission denied
total 0
-r--r--r-- 1 root root 0 Oct 20 20:50 cmdline
-r--r--r-- 1 root root 0 Oct 20 20:50 cpu
lrwx------ 1 root root 0 Oct 20 20:50 cwd
-r-------- 1 root root 0 Oct 20 20:50 environ
lrwx------ 1 root root 0 Oct 20 20:50 exe
dr-x------ 2 egmont pupil 0 Oct 20 20:50 fd
pr--r--r-- 1 root root 0 Oct 20 20:50 maps
-rw------- 1 root root 0 Oct 20 20:50 mem
lrwx------ 1 root root 0 Oct 20 20:50 root
-r--r--r-- 1 root root 0 Oct 20 20:50 stat
-r--r--r-- 1 root root 0 Oct 20 20:50 statm
-r--r--r-- 1 root root 0 Oct 20 20:50 status
egmont $ ##### well, that's it
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.rutgers.edu
Please read the FAQ at http://www.tux.org/lkml/