Under Logical operators, Bash provides logical OR operator that performs boolean OR operation. Bash boolean OR operator takes two operands and returns true if any of the operands is true, else it returns false.
Conditional operators such as -f must be unquoted to be recognized as primaries.When used with [[, the < and > operators sort lexicographically using the current locale.See the description of the test builtin command (in the section "Shell Builtin Commands" below) for the handling of ...
When used with [[, the < and > operators sort lexicographically using the current locale. The test command sorts using ASCII ordering. 即,条件表达式被[[复合命令、test内置命令、和[内置命令用来判断文件属性、进行字符串比较、进行算术比较。 在CONDITIONAL EXPRESSIONS小节中,列举了很多条件表达式,对常用的...
Ascriptis usually saved as a file and executed. Scripting also uses logical operators to test for a condition and then takes action based on the test results. Check for File or Directory Follow the steps below to check if a file or directory exists: 1.Create a scriptfile using atext editor...
If the first number is less than or equal to the second, the condition evaluates to true; otherwise, it evaluates to false. The-leoperator is commonly used in conditional statements likeifandwhile. Examples of-le(Less Than or Equal To) Operator ...
True if either expression1 or expression2 is true. The && and || operators do not evaluate expression2 if the value of expression1 is sufficient to determine the return value of the entire conditional expression. for name [ [ in [ word ... ] ] ; ] do list ; done ...
True if either expression1 or expression2 is true. The && and || operators do not evaluate expression2 if the value of expression1 is sufficient to determine the return value of the entire conditional expression. 变量的基本操作 创建 访问 删除 ┌─[cxxu@cxxuAli] - [~] - [2022-04-27 ...
‘Else if’, or ‘elif’, adds more flexibility to your conditional statements. It allows you to check multiple conditions in a single ‘if’ statement. The script executes the first condition that is true and ignores the rest. Here’s an example of an ‘elif’ statement: ...
Pay special attention to space. There must be space between the opening and closing brackets and the conditions. Similarly, space must be before and after the conditional operators (-le, == etc). Here's what it shows when I run the script: ...
rich set of operators ==, != , >, < compare on strings numeric comparison: -eq, -ge, -ne ... (( expr )): bash arithmetic conditional evaluated as arithmetic expression function # funciton in subshell, does not affect current shell function myfunc ( ... ) # current shell, function...