Common basic commands for Linux 03

Cat
Function: Display all the contents of a file at once
Common options:
-N numbering of all output lines starting from 1
-B is similar to-n, except that it is not numbered for blank lines
-S When you encounter a row that has more than two consecutive lines, replace the blank line with one line
Instance:

[[email protected] ~]# cat 1ntp:x:38:38::/etc/ntp:/sbin/nologinapache:x:48:48:apache:/var/ Www:/sbin/nologinsaslauth:x:498:76:saslauthd user:/var/empty/saslauth:/sbin/nologinxguest:x:500:500:guest :/home/xguest:/bin/bash View the contents of file 1 [[email protected] ~]# cat -n 1      1 NTP:X:38:38::/ETC/NTP:/SBIN/NOLOGIN     2 APACHE:X:48:48: apache:/var/www:/sbin/nologin     3      4  saslauth:x:498:76:saslauthd user:/var/empty/saslauth:/sbin/nologin     5       6      7      8  xguest:x:500:500:guest:/home/xguest:/bin/bash number of rows for all outputs [[email protected] ~]# cat - b 1     1 ntp:x:38:38::/etc/ntp:/sbin/nologin      2 apache:x:48:48:apache:/var/www:/sbin/nologin            3 saslauth:x :498:76:saslauthd user:/var/empty/saslauth:/sbin/nologin                4 xguest:x:500:500:guest:/home/xguest:/bin/bash blank lines not numbered [[email  protected] ~]# cat -s 1ntp:x:38:38::/etc/ntp:/sbin/nologinapache:x:48:48:apache:/var /WWW:/SBIN/NOLOGINSASLAUTH:X:498:76:SASLAUTHD USER:/VAR/EMPTY/SASLAUTH:/SBIN/NOLOGINXGUEST:X:500:500: guest:/home/xguest:/bin/bash[[email protected] ~]#  blank lines that are more than two lines in a row and are substituted for a row

More
Function: Split-screen display of file data, non-disposable display.
Common options:
+n starting from joys N rows
-N defines the screen size as n rows
-C clear the screen from the top and then display
-p to page a file by clearing the window instead of scrolling, similar to the-C option
Instance:

[[email protected] ~]# cat 112345678910 files 1 Total 15 lines of content [[email protected] ~]# more 112345--more--(58%) 678910 starting from the first line, showing a portion of the content, Full screen [[email protected] ~]# SPACEBAR to continue the split screen display or directly display the full file (depending on the number of lines of the file) [[email protected] ~]# more +5 15678910 show from line 5th to end [email Protected] ~]# more-5 112345--more--(47%) 5 rows 5 rows of the display 678910[[email protected] ~]# space bar is continued 5 lines 5 business display, enter is a row of the display

W
Function: Display user login information and system part status
Common options:
General Direct Use W
Instance:

[[email protected] ~]# w12:57:50 up 1 day, 2:49, 1 user, Load average:0.00, 0.00, 0.00USER TTY from   [Email protected] IDLE jcpu PCPU whatroot pts/0 192.168.1.254 Wed10 0.00s 0.58s 0.00s w now date system startup time number of users logged on load

W.H.O.
Role: View current logged in user status
Common options:
WhoAmI See who the current user is
-B Last System boot time
-D print out the death process
-Q shows the number of users who have logged in, and how many users have logged in altogether
-R view running levels now running
Instance:

[[email protected] ~]# whoroot     pts/0         2015-03-18 10:08  (192.168.1.254) root     pts/1         2015-03-19 13:02  (192.168.1.254) jacken    pts/2        2015-03-19 13:12  (192.168.1.254) [[email  Protected] ~]# whoamiroot See who the current user is [[email protected] ~]# who -b          system boot  2015-03-18 10:08 View last system boot time [[email  Protected] ~]# who -d Viewing the death process [[Email protected] ~]# who -qroot root  jacken# users=3 shows the number of users who have logged in, and how many users have logged in altogether [[email protected] ~]# who -r          run-level 3  2015-03-18 10:08[[email  protected] ~]#  Viewing the current RunLevel 

Pwd
Action: Shows the path where the current position is located
Common options:
-P Displays the true path, not the link path.
Instance:

[[email protected] ~]# cd/boot/grub/[[email protected] grub]# pwd/boot/grub Show current location [[email protected] grub]# ln-s/etc . Create a link file when the current directory [[email protected] grub]# CD Etc/[[email protected] etc]# pwd/boot/grub/etc Enter the link file, print out the path [email Protected] etc]# pwd-p/etc print out the location of the real path

This article is from the "Step Into the Linux World" blog, please be sure to keep this source http://linuxnote.blog.51cto.com/9876511/1622740

Common basic commands for Linux 03