The if command executes the statement, and if the exit code of that statement is a zero, the statement is considered true and the if clause is executed. If the exit …
Bash if statements are very useful. In this section of our Bash Scripting Tutorial you will learn the ways you may use if statements in your Bash scripts to help automate tasks. If statements (and, closely related, case statements) allow us to make decisions in our Bash scripts. They allow us to decide whether or not to run a piece of code
So, this seems simple enough, here when only date command runs then only we will get output i.e. “Command works” Also, remember that we can use a number of commands in “then” statement. #!/bin/bash
It is important to remember that the then and fi are considered to be separated statements in the shell. Therefore, when issued on the command line, they are separated by a semi-colon. In a script, the different parts of the if statement are usually well-separated. Below, a couple of simple examples.
The -eq in the statement is an operator or in simpler terms a comparison, it is used to tell bash an operation to perform to find true or false. An if statement is always going to be true or false, either the operator is correct and it is true, or the operator is incorrect and it is false.
In the if/then/elif/else form of the if statement, the first else becomes another if statement or “elif” instead of a simple else. The shell first evaluates condition 1, then condition 2, and so on, stopping with the first condition that succeeds.
The bash scripting language uses this convention to mark the end of a complex expression, such an if-statement or case-statements. The «echo» statement prints its argument, in this case, the value of the variable «count», to the terminal window.
In a bash script, using the conditional “or” in an “if” statement. Ask Question. up vote 74 down vote favorite. 13. This question is a sequel of sorts to my earlier question. Using grep in conditional statement in bash. 0. Bash – issue with grep conditional statement. 1.
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