Shell Programming and Scripting

Dear all,

I would like to know the difference in executing the shell script both ways?

Code:

a.) source file.sh
b.) ./file.sh

I need to initialize some setup which is part of the file.sh. I realized that when I do the

Code:

source file.sh

the setup is all initlaized well. However, with the

Code:

./file.sh

this is not the case.

A bit more of insight as how these commands are different would be really great.

thanking you,
emily

The two are NOT the same...

./script.sh launches the script.sh from the current directory./

However source is identical to . - NOTE the space...

Therefore your alternative is:-

Code:

. ./script.sh

Hope this helps...

EDIT:

From a terminal type:-

Code:

help .

OR...

Code:

help source

Expanding on what wisecracker said, the commands:

Code:

source file.sh
    and
. file.sh

read commands from file.sh and execute them in the current shell execution environment. When the commands from file.sh are completed, any side effects from running those commands (such as setting shell variables) are still in effect in the current shell.

The command:

Code:

./file.sh

creates a new shell execution environment and runs the commands from file.sh in that new environment. When the commands in file.sh have completed, the new shell execution environment terminates and nothing set in that environment affects the current shell execution environment of the shell that invoked ./file.sh.

Thanking you very much, it explain a lot about what I was observing..:-)