可以换成: total=`expr$total +$var` var=`expr$var +1` 下面的循环同理 Until Loop #!/bin/bash var=1total=0until[ $var -gt100];dototal=$((total +var)) var=$((var+1))doneechosumis $total For Loop #!/bin/bash total=0forvarin`seq1100`;dototal=$((total +var))doneechosumis ...
1、罗列式 [code] for VARIABLE in 1 2 3 4 5 .. N do command1 command2 commandN done [/code] [code] #!/bin/bash for i in 1 2 3 4 5 do echo "Welcome $i times" done [/code] 2、使用rang [code] #!/bin/bash for i in {1..5} do echo "Welcome $i times" done [/code...
Loops are very well-known among all basic programming concepts when running a series of instructions or doing some tasks under certain conditions. The most famous and most used loop is the “for” loop. The syntax and working of the “for” loop for a se
1is also tested if it is less than or equal to5, it returns true, and the for loop printsnumber: 1. This process repeats itself until the condition returns false and theforloop exits. #!/bin/bashmax=5printf"Print Numbers from 0 to$max\n"for((x=0;x<=max;x++));doprintf"number...
line done 使用while循环 while read -r line do echo $line done < filename While循环中read命令从标准输入中读取一行,并将内容保存到变量...line中。...在这里,-r选项保证读入的内容是原始的内容,意味着反斜杠转义的行为不会发生。输入重定向...
The second form of for loop is similar to the for loop in ‘C’ programming language, which has three expression (initialization, condition and updation). for (( expr1; expr2; expr3 )) do commands done In the above bash for command syntax, before the first iteration, expr1 is evaluated...
Basically, the simplest for loop syntax repeats the occurrence of a set of a variable. The bash sequence typically looks like this: for VARIABLE in 1 2 3 4 5 .. N Perform the below command: command1 command2 commandN done In the real world, this syntax would look like the example bel...
for n in {1..7}; do echo $n done Once the shell script is executed, all the values in the range are listed, similar to what we had insimple loops. Bash For Loop with Ranges Example Additionally, we can include a value at the end of the range that is going to cause thefor loop...
Number of arguments:1 用户输入 如果你正在为自己或其他人编写Bash程序,那么获取用户输入的一种方式就是指定用户提供给程序的参数,正如我们在前一节中讨论的那样。你还可以通过使用read命令暂时停止程序的执行,要求用户在命令行上输入一个字符串。让我们写一个小脚本,你可以看到read命令是如何工作的: ...
1. 2. 3. Bash For Loop In one Line with variables # for i in $(cat test);do dig $i +short ;done # a="a b c" # for i in $a;do echo $i;done a b c # a=(a b c) # for i in ${a[@]};do echo $i;done