Bash, short for "Bourne Again SHell," is a powerful scripting language used in Unix-based operating systems. One of the fundamental constructs in Bash programming is the if statement. The if statement allows you to control the flow of your script based on specific conditions. In this article,...
问在bash中使用内联if-statement添加命令参数ENexport export命令将会使得被 export 的变量在运行的脚...
This script shows a simple example of anifstatement that uses anelseclause. The conditional test checks whether the customer's age is greater or equal to 21. If it is, the customer can enter the premises, and thethenclause is executed. If they're not old enough, theelseclause is execute...
How to check if a string is in an array? How to use the Bash ternary operator? How to negate an if condition in a Bash if statement? (if not command or if not equal) How to use the BASH_REMATCH variable with the Regular Expression Operator =~?
statement4 . fi If the conditional expression is true, it executes the statement1 and 2. If the conditional expression returns zero, it jumps to else part, and executes the statement3 and 4. After the execution of if/else part, execution resume with the consequent statements. ...
TL;DR: How Do I Use ‘Else If’ in Bash Scripting? 'Else if'in bash scripting, often written as'elif', is used to check multiple conditions in your code. It is used with the syntax,if [firstStatement]; then... elif [secondCondition]; then... else. It’s a powerful tool that ...
linux bash 脚本是个好东西,能用工具搞定的就尽量避免用手敲。这里记录下学习过程中的问题。 1、bash: .../tools.sh: /bin/sh^M: bad interpreter: No such file or directory 这种情况多半是因为,在windows系统中编辑的.sh文件可能有不...
Let's run it again with the same numbers: As you can see, the script is better as it also tells you if the number is odd. Use elif (else if) statement Here's a script that checks whether the given number is positive or negative. In mathematics, 0 is neither positive nor negative....
-e Exit immediately if a simple command (see Section 3.2.1 [Simple Commands], page 8) exits with a non-zero status, unless the command that fails is part of the command list immediately following a while or until keyword, part of the test in an if statement, ...
if [ ! -z err−o!−eapk ]; then 会报出-e无法找到的错误; 而if [ ! -z err]||[!−eapk ]; then 没问题; 整数比较 : -eq 等于,如:if [ "a"−eq"b" ] -ne 不等于,如:if [ "a"−ne"b" ] -gt 大于,如:if [ "a"−gt"b" ] ...