How do I know the script file name in a Bash script?

Question

How can I determine the name of the Bash script file inside the script itself? Like if my script is in file `runme.sh`, then how would I make it to display "You are running runme.sh" message without hardcoding that?

Answer 1

Try $0 e.g.

echo "You are running $0"

Answer 2

Positional Peramaters is the concept your looking for.

There's built-in variables that represent the arguments passed to a script, $1 for the first thing passed, $2 for the second, etc. $# tells you how many.

There's a special Parameter, $0, which represents what your asking about -- the script itself. the zeroth argument.

To be pedantic, and completely thorough this is how man bash describes this parameter:

Special Parameters

"The shell treats several parameters specially. These parameters may only be referenced; assignment to them is not allowed."

0 Expands to the name of the shell or shell script. This is set

at shell initialization. If bash is invoked with a file of com‐

mands, $0 is set to the name of that file. If bash is started

with the -c option, then $0 is set to the first argument after

the string to be executed, if one is present. Otherwise, it is

set to the filename used to invoke bash, as given by argument

zero.