Which two statements correctly describe the type of Information and the behavior of files in the
proc filesystem on Oracle Linux 6?
A.
It is not possible to write to any file in the proc filesystem.
B.
The /proc/cmdline file contains the parameters passed to the kernel.
C.
Each process has a directory named for the process number in the proc filesystem.
D.
The proc filesystem contains the same hardware information that is contained in the sys
filesystem for backward compatibility.
E.
Each process thread has a directory named for the process thread number in the proc
files/stem.
Explanation:
B: proc/cmdline
This file shows the parameters passed to the kernel at the time it is started. A sample
/proc/cmdline file looks like the following:
ro root=/dev/VolGroup00/LogVol00 rhgb quiet 3
Note:
/proc is very special in that it is also a virtual filesystem. It’s sometimes referred to as a process
information pseudo-file system. It doesn’t contain ‘real’ files but runtime system information (e.g.
system memory, devices mounted, hardware configuration, etc). For this reason it can be
regarded as a control and information centre for the kernel. In fact, quite a lot of system utilities are
simply calls to files in this directory.
A,B
A,B
The answer is A,B
==========
Answer: B and C
Not A, because You can change the configuration of the kernel by writing to
certain files that have write permission.
https://access.redhat.com/documentation/en-US/Red_Hat_Enterprise_Linux/3/html/Reference_Guide/ch-proc.html
from man proc
NAME
proc – process information pseudo-file system
DESCRIPTION
The proc file system is a pseudo-file system which is used as an inter‐
face to kernel data structures. It is commonly mounted at /proc. Most
of it is read-only, but some files allow kernel variables to be
changed —> not A
/proc/[pid]/cmdline
This holds the complete command line for the process, unless the
process is a zombie. In the latter case, there is nothing in
this file: that is, a read on this file will return 0 charac‐
ters. The command-line arguments appear in this file as a set
of strings separated by null bytes (‘\0’), with a further null
byte after the last string –> B
/proc/[pid]
There is a numerical subdirectory for each running process; the
subdirectory is named by the process ID. Each such subdirectory
contains the following pseudo-files and directories. —> C
B, C