Function of Shell programming

The definition of the shell function is almost the same as the normal C language function.

function () {

｝

The return value of the Shell function can be displayed, and if there is no return then the execution result of the last statement will be returned as the return value

The return value of a shell function can only be an integer

Example:

Hello ()

｛

echo "You select Hello"

｝

Hello

Shell function calls are not added ()

Examples of function return values:

Hello ()

{

Return 3

}

Hello

Ret=$?

Echo $ret

Examples of function nesting:

Hello ()

｛

echo "Hello"

World

｝

World ()

{

echo "World"
}

Hello

Examples of function parameters

Hello ()

{

Echo $*

}

Hello 1 2 3 4 5

The shell function must be defined before it can be used, otherwise the error

Function of Shell programming