How do I compare two variable values in Unix?
Compare Numbers in Linux Shell Script
- num1 -eq num2 check if 1st number is equal to 2nd number.
- num1 -ge num2 checks if 1st number is greater than or equal to 2nd number.
- num1 -gt num2 checks if 1st number is greater than 2nd number.
- num1 -le num2 checks if 1st number is less than or equal to 2nd number.
How do you compare two variables in a script?
You can use the [ command (also available as test ) or the [[ … ]] special syntax to compare two variables. Note that you need spaces on the inside of the brackets: the brackets are a separate token in the shell syntax.
How do you check if two variables are equal in shell script?
Bash – Check If Two Strings are Equal
- Use == operator with bash if statement to check if two strings are equal.
- You can also use != to check if two string are not equal.
- You must use single space before and after the == and != operators.
Can we compare two variables?
You can compare 2 variables in an if statement using the == operator.
What is the purpose of in Unix?
Unix is an operating system. It supports multitasking and multi-user functionality. Unix is most widely used in all forms of computing systems such as desktop, laptop, and servers. On Unix, there is a Graphical user interface similar to windows that support easy navigation and support environment.
How do I compare two words in a shell script?
Comparison Operators
When comparing strings in Bash you can use the following operators: string1 = string2 and string1 == string2 – The equality operator returns true if the operands are equal. Use the = operator with the test [ command. Use the == operator with the [[ command for pattern matching.
How do you declare a variable in shell?
Unix / Linux – Using Shell Variables
- Defining Variables. Variables are defined as follows − variable_name=variable_value. …
- Accessing Values. To access the value stored in a variable, prefix its name with the dollar sign ($) − …
- Read-only Variables. …
- Unsetting Variables.
How do you set a variable in bash?
The easiest way to set environment variables in Bash is to use the “export” keyword followed by the variable name, an equal sign and the value to be assigned to the environment variable.
What is bin sh Linux?
/bin/sh is an executable representing the system shell and usually implemented as a symbolic link pointing to the executable for whichever shell is the system shell. The system shell is basically the default shell that the script should use.
How do I run a bash script?
Make a Bash Script Executable
- 1) Create a new text file with a . sh extension. …
- 2) Add #!/bin/bash to the top of it. This is necessary for the “make it executable” part.
- 3) Add lines that you’d normally type at the command line. …
- 4) At the command line, run chmod u+x YourScriptFileName.sh. …
- 5) Run it whenever you need!