including if, else, and elif. Then we'll look at a few of the "primary" operators you can leverage in a conditional statement such as = for string equality, -eq for numeric equality, and -e to check if a file e
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,...
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Knowing how conditionals work in bash open up a world of scripting possibilities. We’ll learn the basic syntax, including if, else, and elif. Then we'll look at a few of the "primary" operators you can leverage in a conditional statement such as = for string equality, -eq for numeric...
statement2 ... if(结束) 双分支语句 if 判断条件 then然后 statement 1 statement2 statement3 else否则 statement4 statement5 fi结束 上边的相信估计看不懂,,下边举一个例子: 显示一个用户的是否为系统用户 即ID为0 如果是则输出administrator 不是则 common ...
In this example, we have two variables, ‘a’ and ‘b’. The script checks if ‘a’ is equal to ‘b’. If it’s not, it moves on to the ‘elif’ statement to check if ‘a’ is greater than ‘b’. If neither condition is met, it executes the ‘else’ statement, which in ...
if [ $NUM1 -eq $NUM2 ]; then echo "Both Values are equal" else echo "Values are NOT equal" fi 1. 2. 3. 4. 5. 6. 7. 8. 9. #!/bin/bash # declare integers NUM1=2 NUM2=1 if [ $NUM1 -eq $NUM2 ]; then echo "Both Values are equal" ...
2. if [ 表达式 ] then 语句 else 语句 fi 3. if [ 表达式] then 语句 elif[ 表达式 ] then 语句 elif[ 表达式 ] then 语句 …… fi 例子: a=10 b=20 if [ $a == $b ] then echo "a is equal to b" else echo "a is not equal to b" ...
你所看到的是if语句的第一行,它在检查变量的值是否真的等于12。如果是的话,语句就会停止,并发出numberTwelve is equal to 12的回显,然后在fi之后继续执行你的脚本。如果变量大于12的话,就会执行elif语句,并在fi之后继续执行。当你使用if或if/elif语句时,它是自上而下工作的。当第一条语句是匹配的时候,它会停...
The condition in the IF statement was true, so only the firstechocommand was executed. Now let’s run the program with5as the first argument: bashsimpleelif.sh 5 ## 5 is a great number The first condition is false since 5 is not equal to 4, but then the next condition in the ELIF...