How to run a shell script without changing file access permission

[polymath]

Q. I know chmod command needs to apply to each shell script to make it executable. I’m wondering is if there’s a way to run a shell script without changing file access permission.

A. You can simply use following format
shellname {/path/to/scriptname}
OR
. {/path/to/scriptname}

For example if a shell name is bash and a script name is chkhealth.bash, enter

$ bash chkhealth.bash

OR

$ . chkhealth.bash

Note: dot (,) read and execute commands from given FILENAME and return control to shell.

Other shell examples:

$ ksh /path/to/script.ksh

OR

$ csh /path/to/script.csh

So it is more convenient to invoke the shell with the script as argument. However, I recommend to use chmod command for regular usage:

$ chmod +x script.sh
$ ./script.sh