Now we know what is an if-else function and why is it important for any programmer, regardless of their domain. To understand if-else in shell scripts, we need to break down the working of the conditional function. Let us have a look at the syntax of the if-else condition block. if[...
If-statement-Bash-Script-Example if-else Statement 除了普通的 if 语句之外,我们还可以用 else 块扩展 if 语句。基本思想是,如果语句为真,则执行 if 块。如果语句为假,则执行 else 块。 Syntax : if [ condition_command ] then command1 command2 …….. last_command else command1 command2 …….. ...
1、if语法格式1.1 if格式if condition; then commands; fi1.2 else if 和 elseif condition...
Naturally, this is not optimal. On top of this, involving more advanced shell features such as loops and conditions, we might end up with some complex syntax. 3. Conditional Statements As we’ve already seen, basicif–elsestatements conform to thePOSIXstandard: ...
'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 allows your scripts to make decisions based on various scen...
The basic syntax of a Bashif-elsestatement is as follows: if [ condition ]; then # Code to be executed if the condition is true else # Code to be executed if the condition is false fi Q. How do I use the if-elif-else statement in a bash script to handle multiple conditions?
else echo "Unknown option, ignore it." rm -f $3 exit 5 fi vim + $3 if bash -n $3 &> /dev/null; then chmod +x $3 else echo "Syntax wrong in $3." fi bash测试之文件测试: 操作符 文件路径 -f: 测试其是否为普通文件,即ls -l时文件类型为-的文件; ...
在xshell下,用notepad++写了个简单的shell脚本,内容如下: 1#!/bin/bash23if["X$force"="X1"];then45echo167elif["X$force"="X2"];then89echo21011elif["X$force"="X3"];then1213echo31415else1617echo41819fi 运行报错:syntax error near unexpected token `elif' ...
syntax error near unexpected token `fi' 或是 then 的 shell 的 if else 用法: if ...; then ... elif ...; then ... else ... fi 当运行下面脚本时,如果 if 后的 $a 不加引号,则会报: test.sh: line 5: [: too many arguments 这个错误...
/bin/bash# Description:Syntax rightif[$1-eq0];thenechohelloelseechoworldfi# 这次创建一个正确的脚本,用来检查是否给该脚本添加了执行权限 1. 2. 3. 4. 5. 6. 7. 8. [root@localhost ~]# ls -l /tmp/f.sh -rwxr-xr-x.1root root94Jul1207:40 /tmp/f.sh# 可以看到f.sh这个文件已经有...