Bash Shell Basics

Bash a few common code

######## #最简单的bash

#! /bin/bash    #解析器路径 env                     #查看环境

######### #看运行时间

#!/bin/time. SH start=$ (date +%s) #commands; #statements; Sleep Ten ;               #command End=$ (date +%s) Difference=$ ((End- start))echo time taken To execute $0 is $difference seconds.

########## while loop

#!/bin/-i i= 1sum=0while ((i<=))         do sum + = i + I done echo $ sum       

########## about the interrupt cursor

#!/bin/bash# file name:Sleep.SHEcho-n count:# tput SC storage cursor position tput Sccount=0; while true; Do    if[$count-lt + ];  ThenLet count++; Sleep 1; # The command to restore the cursor position is tput RC tput RC # tput Ed clears all content from the current cursor position to the end of the line tput EdEcho-n $count; ElseExit0; fi Done

########### #shell判断

#! /bin/Bashdeclare-I. num=0if[$num-lt0] There is a space between the #一定要注意在 [or] and the operand Then    Echo "<";elif[$num-eq0 ] Then    Echo "==";Else    Echo ">";fi# [$var 1-ne0-A $var 2-GT2] #使用逻辑与-a# [$var 1-ne0-O VAR2-GT2] #逻辑或-O

########### #shell Debug

#!/bin/bash# file name: Debug. SH  for inch {1.. 6 };  Do -x    echo  $i    +xdone echo      " Script executed "

########### #break

#!/bin/Bash while : Do    Echo-N"Input A number between 1 to 5:"Read Anum Case$aNuminch        1|2|3|4|5)Echo "Your number is $aNum!"                    ;; *)Echo "You does not select a number between 1 to 5, the game is over!"Break ;; Esac Done

############# #case

#! /bin/BashEcho 'Input A number between 1 to 4'Echo 'Your number is:\c'Read Anum Case$aNuminch     1)Echo 'You select 1'             ;; 2)Echo 'You select 2'             ;; 3)Echo 'You select 3'             ;; 4)Echo 'You Select 4'             ;; *)Echo 'You does not select a number between 1 to 4'             ;;Esac

######## #function

function fname () {    echo $1, $2; #访问参数1和参数2    echo" [email protected] " ; #以列表的方式一次性打印所有参数     Echo " $* " ; #类似于 [email protected], but the parameter is used as    a single entity 0  -F fname

Bash Shell Basics