Interacting with Ruby’s runtime environment
In this post I will look at various ways of interacting with a Ruby program’s runtime environment. Following sample program has methods to identify the operating system platform, environment variables in the OS and finding out the command line parameters.
class EnvSample # how to detect operating system platform # check presence of win32 for Windows, linux for Linux etc. def printOSInfo puts RUBY_PLATFORM # RUBY_PLATFORM constant contains OS info end # how to get enviornment variable in Ruby # ENV constant contains a hash of enviornment variables def printEnvVariables puts ENV.inspect end # how to get command line parameters in Ruby # ARGV constant contains command line parameters def printCommandParams puts ARGV.inspect # ARGV[0] represents first parameter end e = EnvSample.new e.printOSInfo # print OS info e.printEnvVariables # print enviornment variables e.printCommandParams # print command line parameters end