What is the equivalent of Java CLASSPATH in Ruby?

Question

I would like to run ruby programs from anywhere. I think I have understood it is RUBYLIB. But I can't make it work. Could you give examples ?

Answer 1

• You need to manupulate the load path $LOAD_PATH ($:)
• This is done with -I directories (Directories are separated by a : on Unix-like systems and by a ; on DOS/Windows systems.)
• You could add -I switches to RUBYOPT ($SAFE must be 0)
• Or with RUBYLIB ($SAFE must be 0 also) which contains search paths.
• RUBYPATH also changes search path for Ruby programs.
• For environment variables, make sure they are proper set or exported so the Ruby VM sees them. You could add a debug print in the ruby.bat or ruby.sh.
• Check your $SAFE setting. If you don't know about it, then its probably fine.

I allways set RUBYLIB and RUBYPATH to my loadpath and add the -S option to the interpreter call.

Answer 2

There is an option -S which looks for the script using PATH environment variable.

for example doing:

ruby -S some_script

Will look for the some_script in current operating system PATH environment variable.

Update: If your script requires other files then use the following statement:

require File.join(File.dirname(__FILE__), "name_of_required_file") 

instead of:

require "name_of_required_path"