linux common commands work

1. echo command

　　echo (option) (variable)

　　Options: -e: translational activation character

　　Use -eoption, if the character appears in the string, then be treated specially, will not it as normal text output:

1. \ A warning sound;
2. \ B before deleting a character;
3. \ C Finally, do not add line breaks;
4. \ F new line but the cursor still remain in the original position;
5. \ N wrap and move the cursor to the first line;
6. \ R cursor to the beginning of the line, but do not wrap;
7. \ T Insert Tab;
8. \ V and \ f the same;
9. \\ inserted into the \ character;
10. \ Nnn insert nnn (octal) ASCII character represented;

　　Printed color text:

　　

　　

Letter color:

echo -e "\e[1;31mThis is red text\e[0m"
This is red text

• \e[1;31m Set the color to red
• \e[0m The color set back again

Color code: Reset = 0, 30 = black, red = 31, green = 32, 33 = yellow, blue = 34, 35 = magenta, cyan = 36, 37 = white

Background color :

echo -e "\e[1;42mGreed Background\e[0m"
Greed Background

Color code: Reset = 0, 40 = black, red = 41, green = 42, 43 = yellow, blue = 44, 45 = magenta, cyan = 46, 47 = white

Flashing text:

echo -e "\033[37;31;5mMySQL Server Stop...\033[39;49;0m"

There are other numerical parameters of the red numbers: 0 Close all attributes, a set of high brightness (in bold), underline 4, 5 flashes, reverse display 7, 8 blanking

2. date command

　　date (option) (parameters)

　　Options:

-d <string>: date and time display string referred to. Before and after the string must be enclosed in double quotes; 
-s <string>: to set the date and time according to the character string. Before and after the string must be enclosed in double quotes; 
-u: GMT display; 
　parameters :

% H hour, 24-hour (00 ~ 23 is) 
% the I hour, 12-hour (01 ~ 12 is) 
% K hour, 24-hour (0 ~ 23 is) 
% L-hour, 12-hour clock (. 1 ~ 12 is) 
% M min (00 ~ 59) 
% P AM or exhibit the PM 
% R & lt time display, 12-hour (HH: mm: SS % P) 
% S from January 1, 1970 to present experience seconds 00:00:00 
% S show seconds (00 ~ 59) 
% T display time, 24-hour (HH: mm: SS) 
% X-display time format (% H:% M:% S) 
% the Z time zone, date field (CST) 
% a week short (the Sun ~ Sat) 
% a week's full name (the Sunday ~ Saturday) 
% H,% B month abbreviation (Jan ~ On Dec) 
% B monthly full name (January ~ December) 
% C date and time (Tue Nov 20 14:12:58 2012) 
% d day of the month (01 ~ 31 is) 
% X,% D date (mm / dd / YY) 
% j day of the year (001 ~ 366) 
% m month (01 ~ 12) 
% w day of (0 for Sunday) a week  
% W the first few weeks of the year (00 to 53, Monday is the first day)
% y last two digits of year (1999 99)
Walk, conversion, output operation delay

　　Addition and subtraction operations

　　

date +% Y% m% d // day before the date display 
date -d "+1 day" +% Y% m% d // day before the date display 
date -d "-1 day" +% Y% m @% d day after the date display 
date -d "-1 month" +% Y% m% d // display the date on January 
date -d "+1 month" +% Y% m% d // display the date of the next month 
date -d "-1 year" +% Y% m% d // display the date one year before the 
date -d "+1 year" +% Y% m% d // display year date

　set time

date -s // set the current time, only root privileges to set up, the other can only view the 
date -s 20120523 // set to 20,120,523, which will set the specific time to empty 00:00:00 
DATE -s 01:01:01 // set a specific time and date will not do to change 
date -s "01:01:01 2012-05-23" // this will set the all-time 
date -s "01:01:01 20120523" // this sets all time 
date -s "2012-05-23 01:01:01" // this will set the all-time 
date -s "20120523 01:01:01" // this will set the all-time 
Note: set the system here time, under normal circumstances with the system hardware time [time] hwclock different 
　　　synchronization time required to install ntpdate, synchronous command: ntpdate, you can also write timing task is completed

3. reboot command

　　reboot (option)

　　

-d: not write record file data / var / tmp / wtmp on reboot. This parameter has a "-n" effect parameter; 
-f: forced reboot, do not call shutdown instruction function; 
-i: before rebooting, close all the network interfaces; 
-n: not before checking whether a reboot is not completed program; 
- w : do only testing the system does not actually reboot, reboot will only write wtmp record data files in / var / log directory.

reboot // reboot. 
reboot -w // to be a reboot of the simulation (only the record does not really reboot

4. poweroff command

　　poweroff (option)

　　

-n: Do not shut down the operating system when performing sync operation; 
- W : not really shut down the operating system, only in the log file "/ var / log / wtmp" in; 
-d: a closed operating system, the operation is not written to a log file "/ var / log / wtmp" added to the corresponding record; 
-f: forcibly shut down the operating system; 
-i: Close all network interfaces before closing the operating system; 
-H: shut down the operating system before the system hardware is provided to all standby mode.

5. wget command

　　Too much trouble, do not want to write

6. ps command

　　-a: display program executed in all terminals, in addition to the steps of the process leader. a: Display all procedures under the existing terminals, including other users of the program.

-A: Show all programs. 
-c: display CLS and PRI fields. 
c: When listing the program, each program displays the name of the real command and does not contain marked path, options or resident services. 
-C <command name>: Specifies the name of the execution of the instruction, and lists the status of the program instructions. 
-d: show all programs, but the program leader of stage work is not included. 
-e: this option is specified the same effect and the "A" option. 
e: when the program lists, for each display environment variables used by the program. 
-f: display UID, PPIP, C and STIME field. 
f: Displays the tree with ASCII characters, expressing the relationship between programs. 
-g <Group Name>: the effect of this option and specify "-G" the same options, can also use the name of the job when the leader of the stage to specify. 
g: Display all procedures under the existing terminals, including the program leader of the group. 
-G <Group ID>: status of belonging to the group are listed in a program, you may also be used to specify the name of the group. 
h: do not display the title bar. 
-H: displays a tree structure showing the relationship between programs. 
-j or j: the use of job control format display program status. 
or -l l: using the detailed status display program format. 
L: list information field. 
-m or m: Display all the threads. 
n: with numbers to represent USER and WCHAN field. 
-N: display all programs other than the program in addition to the terminal under the instruction execution ps. 
-p <program identification code>: Specifies the program identification code, and lists the status of the program. 
p <program identification code>: This option effect and designated "-p"
r: lists only the current program being executed in the terminal.
-s <stage job>: Specifies the program identification code phase of the job, and lists the membership status of the phase of the job program. 
s: program using the program status signal format. 
S: When listing procedures, including the interrupted routine information. 
-t <terminal ID>: Specifies the terminal number, and lists the status of belonging to the terminal program. 
t <terminal number>: same effect and specify this option "-t" option, only a slight difference in the list of formats. 
-T: displays all the programs under the current terminal. 
-u <user ID>: the same effect and specify this option "-U" option. 
u: user-based format to display program status. 
-U <user ID>: status lists belonging to the user program, can also be used to specify the name of the user. 
U <user name>: lists the status of belonging to the user program. 
v: virtual memory format display program status. 
-V or V: Display version information. 
- W or w: using wide format display program status.　
x: Show all programs, the terminal is not to be distinguished. 
X: using the old Linux i386 landed format display program status. 
-y: with the option "-l" When in use, do not show F (flag) field, and RSS fields to replace ADDR field. 
- <program identification code>: this option is specified, and the same effect of the "p" option. 
--cols <number of characters per row>: Sets the maximum number of characters per column. 
--columns <
--cumulative: the same effect and specify this option "S" option. 
--deselect: effects and specify this option "-N" the same options. 
--forest: the effect of this option and specify "f" of the same options. 
--headers: Repeat display the title bar. 
- Help : online help.  - info : displays troubleshooting information.  --lines <shows the number of columns>: setting display screen is the number of columns.  --no-headers: the effect of this option and specify "h" the same options, only a slight difference in the list of formats.  --group <Group Name>: same effect and specify this option "-G" option.  --Group <Group ID>: the same effect and this option designated "-G" option.  --pid <program identification code>: the same effect and this option designated "-p" option.  --rows <shows the number of columns>: the same effect and this option designated "--lines" option.  --sid <stage operation>: This option is the same effect and designated the "-s" option.  --tty <terminal number>: same effect and specify this option "-t" option.  --user <username>: same effect and specify this option "-U" option.  --User <user ID>: the same effect and specify this option "-U" option.  --version: This option's effect and specify "

　　The results of this command may be very long. For ease of viewing, and the pipe may be combined to use less command.

　　$ ps -ax | less

2. The user filtering process

　　In the case of the need for specific user processes, we can use the -u parameter. For example, we want to see users 'pungki' process, you can use the following command:

$ Ps -u pungki

 

 

7. top command

-b: in batch mode; 
-c: display the full rule command; 
-d: Screen refresh interval; 
the -I: ignore the failure process; 
-s: privacy mode; 
-S: Cumulative mode; 
-i <time> : set the interval; 
-u <user name>: Specifies the user name; 
-p <process ID>: Specifies the process; 
-n <number>: the number of times to cycle through 
the interactive command:

h: Help screen is displayed, the command is given a brief summary of some description; 
k: terminate a process; 
i: Ignore idle and zombie process, which is a switch-type command; 
q: exit the program; 
r: re-arrange the priority of a process ; 
S: switching to the accumulation mode; 
S: change the delay time between two refreshes (in s), if there is a decimal, it is converted into ms. Input 0 value, the system will continue to refresh, the default value is 5S; 
F or F: add or remove items from the currently displayed; 
O or O: changing the order of the displayed items; 
L: switching display the average load and start time information; 
m: toggle display of memory information; 
T: switch the display process and CPU state information; 
C: switching the display name and full command line command; 
M: sorted according to the size of the memory-resident; 
P: using the percentage of sorted according to size CPU; 
T: The time / total time for sorting; W : write current settings ~ / .toprc file.

8. pidof command

　

9. The kill command

-a: When dealing with the current process, the process does not limit the number of command names and corresponding relationship; 
-l <message number>: If left <message number> option, the -l option will list the names of all of the information; 
-p: Specifies the kill command to print only the process ID related processes, without sending any signal; 
-s <message name or number>: Specifies the information to be sent; 
-u: Specifies the user.

-ef PS | grep vim 
root 3268 2884 0 16:21 PTS / 1 00:00:00 vim install .log 
root 3370 2822 0 16:21 PTS / 0 00:00:00 grep vim 

the kill 3268 
the kill 3268 
-bash: the kill : (3268) - do not have that process

10. killall command

-e: a long name for an exact match; 
the -l: Ignore different capitalization; 
-p: process group to kill the process belongs; 
-i: Interactive kill the process, kill the process before need to be acknowledged; 
the -l: Print a list of all known signal; 
-q: if no processes were killed. Not output any information; 
-r: Use regular expression matching process name to kill; 
-s: instead of using the default specified process ID signal "SIGTERM"; 
-u: kill the specified user process.

Kill all processes with the same name

killall we