For this, we need to utilize the not operator “!” with the “if” statement in the bash script. Let’s discuss the use of the “if-not” operator in Bash programming with the help of some examples. Get started with the new Bash file creation while using the terminal shell of the ...
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In this example, the script first checks if ‘a’ is greater than ‘b’. If it’s not, it moves on to the ‘elif’ statement to check if ‘a’ is greater than ‘c’. If neither condition is met, it executes the ‘else’ statement, which in this case, prints ‘a is not greate...
1. Bash If..then..fi statement if [ conditional expression ] then statement1 statement2 . fi This if statement is also called as simple if statement. If the given conditional expression is true, it enters and executes the statements enclosed between the keywords “then” and “fi”. If th...
Example 7: If Else Statement in Bash Scripting We will now demonstrate theELSEcondition. TheELSEcondition is used in the case where theIFcondition or all theELIFconditions do not exist then theELSEcondition will be used and the code in theELSEcondition will be executed. Let’s add an example...
Check to see if a variable is empty or not Create a new bash file, named, and enter the script below. The script above stores the first command-line argument in a variable and then tests the argument in the next statement. This script will print the first argument because it is not em...
-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" ] -ge 大于等于,如:if [ "a"−ge"b" ] -lt 小于,如:if [ "a"−lt"b" ] -le 小于等于,如:if [ "a"−le"b" ] ...
if语句的单分支结构: if 命令; then 命令; fi 注意:是否会执行then后面的命令,取决于if后面的命令的执行状态返回值; 1.如果返回值为真,则执行后面的命令; 2.如果返回值为假,则不执行后面的命令; 书写形式两种: if CONDITION ; then STATEMENT ... ...
!=: Not equal to -z: Empty string -n: Non-empty string 3. File and Directory Checks: -e: Exists -f: Regular file -d: Directory -r: Readable -w: Writable -x: Executable Example of using If Statement: Let’s illustrate the usage of if statements with a few examples: ...
statementBlock of code that gets executed depending on the result of a condition.echo "You are not eligible" elifThese are used to add more conditions and statements to an if statement.elif [ condition2 ]; then nested ifCreating a if statement inside an if statement. Or in other words, ...