To view a list of all the files which the process with process ID PID is keeping open, use the parameter -p. For example, to view all the files used by the current shell:
$ 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. Usually a huge number of files will be open. To find out how many files are open, enter the following:
$ lsof | wc -l 3749
List of all the character devices used:
$ 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