Chapter 2. The

proc

File System

39

4. Number of pages are code

5. Number of pages of data/stack

6. Number of pages of library

7. Number of dirty pages

  status

  The status of the process in a more readable form than

stat

or

statm

. Sample output

for

sshd

looks similar to this:

Name: sshd

State: S (sleeping)

Tgid: 797

Pid: 797

PPid: 1

TracerPid: 0

Uid: 0 0 0 0

Gid: 0 0 0 0

FDSize: 32

Groups:

VmSize:

3072 kB

VmLck:

0 kB

VmRSS:

840 kB

VmData:

104 kB

VmStk:

12 kB

VmExe:

300 kB

VmLib:

2528 kB

SigPnd: 0000000000000000

SigBlk: 0000000000000000

SigIgn: 8000000000001000

SigCgt: 0000000000014005

CapInh: 0000000000000000

CapPrm: 00000000fffffeff

CapEff: 00000000fffffeff

Other than the process's name and ID, the state (such as

S (sleeping)

or

R (running)

and

user/group ID running the process is available, as well as much more detailed data regarding mem 

ory usage.

2.3.1.1.

/proc/self/

The

/proc/self/

directory is a link to the currently running process. This allows a process to look

at itself without having to know its process ID.

Within a shell environment, a listing of the

/proc/self/

directory produces the same contents as

listing the process directory for that process.

2.3.2.

/proc/bus/

This directory contains information specific to the various buses available on the system. So, for

example, on a standard system containing ISA, PCI, and USB busses, current data on each of these

buses is available in its directory under

/proc/bus/

.

The contents of the subdirectories and files available varies greatly on the precise configuration of

your system. However, each of the directories for each of the bus types has at least one directory for

each bus of that type. These individual bus directories, usually signified with numbers, such as

00

,

contains binary files that refer to the various devices available on that bus.