lunix shell 基础经常使用整理

 1   ps  -ef    显示正在执行的进程，pid 等信息

 UID PID PPID C STIME TTY TIME CMD

root 1 0 0 03:45 ? 00:00:02 init [5]

root 2 1 0 03:45 ?

00:00:00 [migration/0]

root 3 1 0 03:45 ? 00:00:00 [ksoftirqd/0]

root 4 1 0 03:45 ? 00:00:00 [events/0]

root 5 1 0 03:45 ?

00:00:00 [khelper]

root 6 1 0 03:45 ? 00:00:00 [kthread]

root 9 6 0 03:45 ?

00:00:00 [kblockd/0]

root 10 6 0 03:45 ? 00:00:00 [kacpid]

2   df    -h    可读显示磁盘空间   M是兆

Filesystem Size Used Avail Use% Mounted on

/dev/sda2 18G 5.0G 12G 31% /

/dev/sda1 289M 16M 258M 6% /boot

tmpfs 506M 0 506M 0% /dev/shm

3  借助df命令，能够方便地了解磁盘是否已空间不足，系统管理员须要了解空间不足时该怎么办。

 我们能够使用du命令 ，du命令显示特定文件夹的磁盘使用情况，这是推断系统是否存在磁盘

占用大户的快捷方法。

du    ,   du  -h（显示M。G单位）  ,du  -c （汇总），du  -s（汇总全部。仅仅显示一个）

du [ -a | -s ] [ -k ] [ -m ] [ -g ][ -l ] [ -r ] [ -x ] [ -H | -L ][ File ... ] 

8.0K ./test_flume/.flumespool

24K ./test_flume

8.0K ./mnt

58M ./awk

28K ./shell

18M ./spark

76M .

4   sort  （排序）  sort  file.txt

默认按字符排序

数字排序   sort -n  file.txt

sort -n file2

0

2

3

5

6

7

9

17

sort  -M  file3.txt  (依照月份排序)

sort -t ':' -k 3 -n /etc/passwd  按指定分隔符':" 第三个字段进行排序  按数字排序的

du -sh * | sort -nr  按空间占用从大到小 排序  包含目录和文件    r是指降序排列

5   gzip ：用于压缩文件

gzip  2.sh

gzip  file*

gzip -r  test1  test2  压缩2个文件

tar  -cvf  my.tar  my.sh    tar压缩

tar -xvf  my。

tar      tar解压

tar  -zxvf filename.tgz

7 打印环境变量

  printenv 

bash

test=testing

echo $test

7  finger  llisc

/usr/sbin/groupadd shared

/usr/sbin/usermod -G shared test

文件权限表    755 

chmod o+r  newfile 

将条目读取加入到不论什么人

chmod u-x newfile 

将条目山下湖用户拥有的运行权限

chmod u+x newfile 

chown  改动用户文件拥有者 和所在组

9 shell  

rpm  -qa | sort  | more 

echo $?

if   表达式  返回0  运行成功

then

fi

if   test [ condition ]

for  var  in Li72 Alibaba taobao Newbatilr

do

  echo the state $test

done

使用转移字符反斜杠符合来转移单引號

使用双引號来定义单引號的值

#!/bin/bash

for file in /home/bigdata/test/*  /home/li75/

do

  if [ -d "$file" ]

then

  echo "$file is a directory "

elif [ -f "$file" ]

then

  echo "$file is a file "

fi

done

#!/bin/bash

for(( i=1; i<= 10; i++))

do

 echo " The next number is $i"

done

#!/bin/bash

 var1=10

while [ $var1 -gt 0 ]

do

  echo $var1

  var1=$[ $var1 - 1 ]

done

#!/bin/bash

var1=100

until [ $var1 -eq 0 ]

do

 echo $var1

  var1 =$[ $var1 -25 ]

done

#!/bin/bash

for((a =1; a<=3; a++))

do

  echo "starting loop $a:"

for((b=1;b<=3;b++))

  do

  echo " inside loop: $a*$b "

done

done

break

contince

#!/bin/bash

for(( a=1; a<4 ;a++))

do

  echo "Outer loop :$a"

 for((b=1;b<100;b++))

do

 if [ $b -gt 4 ]

then

  break 2

fi

echo "Inner loop :$b"

done

done > test.txt   重定向到一个文件

        |  sort   排序

參数

 位置參数

$0 为为程序名称

 $1 为第一个參数

$2 为第二个參数

$3 为第三个參数

#!/bin/bash

factorial=1

for((number =1;number<= $1;number++))

do

  factorial=$[ $factorial * $number ]

done

echo  The factorial of $1 is  $factorial

name =` basename $0`

获取执行shell 脚本名称

if   [ -n "$1" ]

推断有没有传入參数

if  [ $# <5 ]

推断传入參数个数

 获取最后一个參数的值

 params =$#

echo  parm : $params

或者

The  last   paramer ${!#}   

  $* 把全部的參数当作一个參数

  $@ 把全部參数当作字符串  分开处理

#!/bin/bash

while [ -n "$1" ]

 do

    case  "$1" in

-a) echo "Found the -a  option" ;;

-b) echo "Found the -b option" ;;

-c) echo "Found the -c option";;

*) echo "$1 is not an option";;

  esac

 shift

done

#!/bin/bash

echo -n 'Enter your name :"

read name

echo "Hello $name,  welcome to my prorram ."

#!/bin/bash

read -p "Please enter your age :" age

days =$[ $age * 365 ]

echo " That makes you over $days days old !"

ls -al test test22 test3 badtest &>test7

#!/bin/bash

echo "This is an error " >&2

echo "This is normal output "

#!/bin/bash

exec 1>testout

echo "This is a test of redirting all output"

echo "without having to redirect every line "

#!/bin/bash

exec 2>testerror

echo "This is the start of the script"

echo "now reidirecting all output to another "

exec 1>testout2

echo "This putput should go to the "

echo "but shis should go to testerror file >&2

#!/bin/bash

exec 0<testfile2

count=1

while read line

do

   echo "Line #$count :$line"

  count=$[ $count +1 ]

done

lsof -a -p $$ -d 0,1,2

重定向到空文件  

ls -al >/dev/null

cat /dev/null > testfile 

同一时候记录文件和打印到屏幕

date | tee testfile

追加数据

date | tee -a testfile

kill -9   进程id

#!/bin/bash

trap "echo HaHa " SIGINT SIGTEERM

echo "THis is a test program "

count=1

while [ $count -le 10 ]

do

  echo "Loop #$count"

sleep 10

count=$[ $count +1  ]

done

 echo "This is the end of test program "

把命令在后台执行用  &

sh 37.sh &

ps  au

有时须要从终端启动会话，然后让脚本在结束之前以后台模式执行，即使退出终端会话有时如此

能够用nohup

jobs

jobs -r

jobs -s

jobs -l

nice  设置优先级

nice -n 10 sh 38.sh >test4out &

at  命令

batch  命令

cron  表格

#!/bin/bash

time=`date +%T`

echo "This script ran at $time "

echo "This is the end of the script">&2

corn   表格使用特殊格式制定作业的时间。

15 10 * * * command

查看登陆用户配置的定时任务

crontab -l 

编辑任务

corntab -e 

#!/bin/bash

function func1 {

  echo 'This is an example of a function"

  }

count=1

while [ $count -le 5 ]

do

 func1

 count=$[ $count +1 ]

done

 echo "This is the end of the loop"

func1

 echo "Now  this is the end of the script "

函数的返回值

$?

#!/bin/bash

func1(){

echo "trying to display a non"

ls -ls 41.sh

}

echo "testing the function:"

func1

echo "The exit status is :$?

"

#!/bin/bash

function db1 {

read -p "Enter a value :" value

 echo "doubling the value "

 return $[ $value * 2 ]

}

db1 

echo "The new value is $?"

函数返回值

#!/bin/bash

function db1{

read -p "Enter a value :" value

echo $ [ $value *2 ]

}

result='db1'

echo 'The new value is $result"

提供函数文件

   能够用source  命令或称（点操作符）将现有的库函数引进.bashrc中

source   /home/li72/libraries/myfuncs

.    /home/li72/libraries/myfuncs

function addem   {

echo $[ $1 +$2 ]

}

function multem {

  echo $[ $1 * $2 ]

}

function divem {

  if [ $2 -ne 0 ]

  then 

   echo $[ $1 /$2 ]

else 

   echo -1

fi

}

#!/bin/bash

. ./myfuncs

result=`addem 10 16`

echo "The result is $result"

.bashrc  每次启动shell 都会检查该文件  ，在已有文件的末尾加入自己定义函数

.  /home/bigdata/test/shell/myfuncs

文本处理

sed    luinx 编辑替换

gawk

echo "This is a test " | sed 's/test/big test/'

cat>dog.txt

The  quick brown fox jumps over the lazy dog .

The  quick brown fox jumps over the lazy dog .

The  quick brown fox jumps over the lazy dog .

The  quick brown fox jumps over the lazy dog .

The  quick brown fox jumps over the lazy dog .

sed 's/dog/cat/' dog.txt    

The quick brown fox jumps over the lazy cat .

The quick brown fox jumps over the lazy cat .

The quick brown fox jumps over the lazy cat .

The quick brown fox jumps over the lazy cat .

The quick brown fox jumps over the lazy cat .

sed -e '

> s/brown/green/

> s/fox/elephant/

> s/dog/cat/' dog.txt

The quick green elephant jumps over the lazy cat .

The quick green elephant jumps over the lazy cat .

The quick green elephant jumps over the lazy cat .

The quick green elephant jumps over the lazy cat .

The quick green elephant jumps over the lazy cat .

从文件读取编辑器命令

 cat>script

s/brown/green/

s/fox/elephant/

s/dog/cat/

sed -f script dog.txt

The quick green elephant jumps over the lazy cat .

The quick green elephant jumps over the lazy cat .

The quick green elephant jumps over the lazy cat .

The quick green elephant jumps over the lazy cat .

The quick green elephant jumps over the lazy cat .

cat>script2

{print $5 "'s userid is " $1 }

加入用户

useradd xuhui

改动password

usermod  -p xuhui xuhui

查看password文件

tail -l /etc/shadow

cd -  返回上一个訪问的文件夹

查找文件命令

find  [路径]  [选项]  [操作]

find . -name 'test*'    查找 文件名为 test开头的

find . -mtime -90 -print  查找更改时间在90天内的文件

grep  [选项]  [模式]  [文件]

在wodl.txt  找World单词

grep -w  'World' wodl.txt