在Bash脚本,有3种类型loops:for loop,while loop, 和until loop. 这三个用于迭代值列表并执行一组给定的命令。 Bash For 循环语法 for loop遍历一系列值并执行一组命令。 For loop采用以下语法: forvariable_name in value1 value2 value3..ndocommand1 command2 commandn done 1. 2. 3. 4. 5. 6. Ba...
Hopefully, these examples have demonstrated the power of aloop at the Bash command line. You really can save a lot of time and perform tasks in a less error-prone way with loops. Just be careful. Your loops will do what you ask them to, even if you ask them to do something destructi...
Why you can use a bash for loop in one line If you use bash on the command line, this will not guarantee that for loops are inserted into the script. In order to prevent this, it is easiest to use loops directly on the command line and then there will be no problems. How to use...
Bash For Loop In one line with Command Output # for i in `seq 1 5`;do echo $i ;done # for i in `cat test`;do dig $i +short ;done # for i in `awk '{print $1}' test` ;do ping -c 2 $i ;done Bash For Loop In one Line with variables # for i in $(cat test);do...
Standard Bash For Loop Over Strings Over a Number Range Over Array Elements Break and Continue for Loop Break Statement Continue Statement Examples of Bash for Loops Share Loops are one of the most powerful and fundamental programming concepts that allow users to execute a command or set of ...
commandN done 1. 2. 3. 4. 5. 6. OR for OUTPUT in $(Linux-Or-Unix-Command-Here) do command1 on $OUTPUT command2 on $OUTPUT commandN done 1. 2. 3. 4. 5. 6. Examples This type of for loop is characterized by counting. The range is specified by a beginning (#1) and ending...
For example, you can run UNIX command or task 5 times or read and process list of files using a for loop. A for loop can be used at a shell prompt or within a shell script itself. for loop syntax Numeric ranges for syntax is as follows: ...
echo "endless loop" done 可以在 if/then 中作占位符: #!/bin/bash condition=5 if [ $condition -gt 0 ] #gt表示greater than,也就是大于,同样有-lt(小于),-eq(等于) then : # 什么都不做,退出分支 else echo "$condition" fi 变量扩展/子串替换 ...
Bash For Loop Syntax 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 ...
# For loop for i in {1..5}; do echo “Number: $i” done # While loop counter=1 while [[ $counter -le 5 ]]; do echo “Counter: $counter” counter=$((counter+1)) done “` 以上是编写 Bash 脚本的一些建议和示例。当然,还有很多其它功能和语法可以用于编写 Bash 脚本,这只是一个入门...