Part IV. Administration / Chapter 36. System Monitoring Utilities | ||||
|---|---|---|---|---|
 | 35.5. For More Information | 36.2. User Accessing Files: fuser |  | |
Part IV. Administration / Chapter 36. System Monitoring Utilities | ||||
|---|---|---|---|---|
| 35.5. For More Information | 36.2. User Accessing Files: fuser | | |
Table of Contents
/proc File SystemAbstract
A number of programs and mechanisms, some of which are presented here, can be used to examine the status of your system. Also described are some utilities that are useful for routine work, along with their most important parameters.
For each of the commands introduced, examples of the relevant
outputs are presented. In these examples, the first line is the
command itself (after the dollar sign prompt). Comments
are indicated with square brackets ([...])
and long lines are wrapped where necessary. Line breaks for long
lines are indicated by a backslash (\).
$ command -x -y
output line 1
output line 2
output line 3 is annoyingly long, so long that \
we have to break it
output line 3
[...]
output line 98
output line 99
The descriptions have been kept short to allow as many
utilities as possible to be mentioned. Further information for all
the commands can be found in the man pages. Most of the commands
also understand the parameter
--help, which produces a brief list of the
possible parameters.
To view a list of all the files open for the process with process ID
PID, use
-p. For example, to view all the files used by the
current shell, enter:
$ lsof -p $$ COMMAND PID USER FD TYPE DEVICE SIZE NODE NAME zsh 4694 jj cwd DIR 0,18 144 25487368 /suse/jj/t (totan:/real-home/jj) zsh 4694 jj rtd DIR 3,2 608 2 / zsh 4694 jj txt REG 3,2 441296 20414 /bin/zsh zsh 4694 jj mem REG 3,2 104484 10882 /lib/ld-2.3.3.so zsh 4694 jj mem REG 3,2 11648 20610 /usr/lib/zsh/4.2.0/zsh/rlimits.so [...] zsh 4694 jj mem REG 3,2 13647 10891 /lib/libdl.so.2 zsh 4694 jj mem REG 3,2 88036 10894 /lib/libnsl.so.1 zsh 4694 jj mem REG 3,2 316410 147725 /lib/libncurses.so.5.4 zsh 4694 jj mem REG 3,2 170563 10909 /lib/tls/libm.so.6 zsh 4694 jj mem REG 3,2 1349081 10908 /lib/tls/libc.so.6 zsh 4694 jj mem REG 3,2 56 12410 /usr/lib/locale/de_DE.utf8/LC_TELEPHONE [...] zsh 4694 jj mem REG 3,2 59 14393 /usr/lib/locale/en_US/LC_NUMERIC zsh 4694 jj mem REG 3,2 178476 14565 /usr/lib/locale/en_US/LC_CTYPE zsh 4694 jj mem REG 3,2 56444 20598 /usr/lib/zsh/4.2.0/zsh/computil.so zsh 4694 jj 0u CHR 136,48 50 /dev/pts/48 zsh 4694 jj 1u CHR 136,48 50 /dev/pts/48 zsh 4694 jj 2u CHR 136,48 50 /dev/pts/48 zsh 4694 jj 10u CHR 136,48 50 /dev/pts/48
The special shell variable $$, whose value is the
process ID of the shell, has been used.
The command lsof lists all the files currently open when used without any parameters. Because there are often thousands of open files, listing all of them is rarely useful. However, the list of all files can be combined with search functions to generate useful lists. For example, list all used character devices:
$ lsof | grep CHR sshd 4685 root mem CHR 1,5 45833 /dev/zero sshd 4685 root mem CHR 1,5 45833 /dev/zero sshd 4693 jj mem CHR 1,5 45833 /dev/zero sshd 4693 jj mem CHR 1,5 45833 /dev/zero zsh 4694 jj 0u CHR 136,48 50 /dev/pts/48 zsh 4694 jj 1u CHR 136,48 50 /dev/pts/48 zsh 4694 jj 2u CHR 136,48 50 /dev/pts/48 zsh 4694 jj 10u CHR 136,48 50 /dev/pts/48 X 6476 root mem CHR 1,1 38042 /dev/mem lsof 13478 jj 0u CHR 136,48 50 /dev/pts/48 lsof 13478 jj 2u CHR 136,48 50 /dev/pts/48 grep 13480 jj 1u CHR 136,48 50 /dev/pts/48 grep 13480 jj 2u CHR 136,48 50 /dev/pts/48
