Linux command for a ruby script

Question

how could I run a ruby script as a command in linux.

I have this script which access the lib but i have to run it as

teraData.rb

i want to run it as teradata (or some meaningful command ) with args on linux from any command promt.

Where should i place the script and what should I do?

I am kinda new to linux so please help

Answer 1

If the script is executable and the first line of the script is #!/usr/bin/ruby (or whatever the path to your ruby interpreter might be), then you should be able to launch the script directly (i.e. $ ./myscript.rb).

Otherwise, execute the interpreter and pass it the script as an argument (ruby ./myscript.rb).

If you want to run the script from anywhere using a simple command, wrap one of these methods in a bash function like so:

function teraData {
 ruby /path/to/script/teraData.rb $*
}

Place this function definition in your .bashrc file to have it automatically loaded whenever you open a shell.

• sarnold: While it's useful to learn about shell functions, I think it should be noted that the .rb suffix on the file isn't necessary, and if the script is placed into a directory on the PATH, there's no need for the shell function.
• user384070: I have put the directory in the PATH but i still have to type teraData.rb .I want a shell script/command like ls .
• Tim McNamara: @user384070 You should click on the tick to the left of this answer :)
• bta: @user384070- Does the shell function I listed not provide the functionality that you want? It should allow you to launch the script by typing teraData <your arguments> from any directory.
• bta: @user384070- Alternatively, if you can launch the script by typing ./teraData.rb you should be able to create a symlink to the script and name it whatever you want (place the symlink in your PATH instead of the script).

Answer 2

put this as the first line of the script:

#!/usr/bin/env ruby

Answer 3

write a shell script that invokes the ruby script. Make sure both are executable.

• sarnold: Pointless use of a shell script. Ruby is an interpreted language that supports the standard #!/usr/bin/ruby.

Answer 4

As you're new to linux, I recommend:

$ cd /path/to/file
$ ruby ./teraData.rb

Once you gain confidence, it's also possible to just enter the filename in the shell prompt. To do this, you need to:

1. change the first line of teraData.rb to #! /usr/bin/env ruby (this will find the correct executable for you, other first lines are possible)
2. change the permissions of the file, to allow it to execute: chmod +x teraData.rb