# Beginner Ruby Question **URL:** \ **Category:** Ruby\ **Created:** [May 18, 2009, 8:31pm UTC](https://www.ruby-forum.com/t/beginner-ruby-question/168258 "2009-05-18T20:31:07Z")\ **Posts on this page:** 7\ **Page:** 1
**Author:** ![calvin](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/c/f475e1/32.png) [@calvin](https://www.ruby-forum.com/u/calvin)\ **Post date:** [May 18, 2009, 8:31pm UTC](https://www.ruby-forum.com/t/beginner-ruby-question/168258/1 "2009-05-18T20:31:07Z")
Hi, I just intstalled Ruby 1.9 on my mac with macports. The installation was successful but when I type in ruby -v at the command prompt, Ruby 1.8.6 shows up still. The latest Pickaxe book says I have to have /opt/ local/bin in my path to add it… but don’t really get how that’s supposed to work. Thanks for your time, Calvin ---
**Author:** ![calvin](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/c/f475e1/32.png) [@calvin](https://www.ruby-forum.com/u/calvin)\ **Post date:** [May 18, 2009, 8:41pm UTC](https://www.ruby-forum.com/t/beginner-ruby-question/168258/2 "2009-05-18T20:41:23Z")
Calvin wrote: > I just intstalled Ruby 1.9 on my mac with macports. The installation > was successful but when I type in ruby -v at the command prompt, Ruby > 1.8.6 shows up still. The latest Pickaxe book says I have to have /opt/ > local/bin in my path to add it… but don’t really get how that’s > supposed to work. You should be able to use your new ruby by its full path name: $ /opt/local/bin/ruby --version ruby 1.9.1p0 (2009-01-30 revision 21907) [i386-darwin9] To make that the Head Ruby In Charge, try this: echo ‘export PATH="/opt/local/bin:$PATH"’ \>\> ~/.profile export PATH="/opt/local/bin:$PATH" hash -r You should then see the right ruby by default: $ which ruby /opt/local/bin/ruby ---
**Author:** ![calvin](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/c/f475e1/32.png) [@calvin](https://www.ruby-forum.com/u/calvin)\ **Post date:** [May 18, 2009, 10:27pm UTC](https://www.ruby-forum.com/t/beginner-ruby-question/168258/3 "2009-05-18T22:27:11Z")
On May 18, 11:36 am, Jeff S. [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote: > ruby 1.9.1p0 (2009-01-30 revision 21907) [i386-darwin9] > /opt/local/bin/ruby > I tried it out but I am having trouble when I type in: echo ‘export PATH=“/opt/local/bin:$PATH”’ \>\> ~/.profile nothing happens if I type in: echo ‘export PATH=“/opt/local/bin:$PATH”’ i get: export PATH=“/opt/local/bin:$PATH” on the terminal screen and when i type in: hash -r the terminal says -r isn’t valid Would you be able to break things down into simpler steps or describe what you type in and in what order… i know you already kinda did that but I am new to using the terminal and would appreciate it alot. Thanks again for your time… sorry for bothering you about this stuff but [hivelogic.com](http://hivelogic.com) is down today for some reason. ---
**Author:** ![calvin](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/c/f475e1/32.png) [@calvin](https://www.ruby-forum.com/u/calvin)\ **Post date:** [May 18, 2009, 10:52pm UTC](https://www.ruby-forum.com/t/beginner-ruby-question/168258/4 "2009-05-18T22:52:00Z")
echo ‘export PATH="/opt/local/bin:$PATH"’ \>\> ~/.profile adds ‘export PATH="/opt/local/bin:$PATH"’ to the end of your ~/.profile which probably is where your shell setup info is stored. try looking at ~/.profile – the export PATH stuff should be at the end of the file. Adding it to ~/.profile adds /opt/local/bin to the path on login, and the ‘hash -r’ should have reevaluated the ~/.profile and added the changes. If you just want to try it without all that, you could just do export PATH="/opt/local/bin:$PATH" which will add /opt/local/bin to the path. then ruby -v should be 1.9 assuming the binary is in /opt/local/bin. Nick ---
**Author:** ![calvin](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/c/f475e1/32.png) [@calvin](https://www.ruby-forum.com/u/calvin)\ **Post date:** [May 18, 2009, 11:16pm UTC](https://www.ruby-forum.com/t/beginner-ruby-question/168258/5 "2009-05-18T23:16:15Z")
Calvin wrote: > On May 18, 11:36 am, Jeff S. [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote: > > > Calvin wrote: > > > > > I just intstalled Ruby 1.9 on my mac with macports. The installation > > > was successful but when I type in ruby -v at the command prompt, Ruby > > > 1.8.6 shows up still. The latest Pickaxe book says I have to have /opt/ > > > local/bin in my path to add it… but don’t really get how that’s > > > supposed to work. > when I type in: echo ‘export PATH=“/opt/local/bin:$PATH”’ \>\> > ~/.profile > nothing happens You’re not supposed to see anything happen, except that the shell should prompt you for the next command. I’m assuming you’re using “bash” (Bourne Again SHell), the default command-line shell on Mac OS X (and most Linux distros). Since “hash -r” is not working, you may not be using bash, after all. The next most likely candidate is called tcsh. What do you see when you run this? ``` echo $SHELL ``` It’s also traditional for different shells to use different prompts. Bash uses $, csh uses %, and tcsh uses % or \>. As a special case, the root user’s prompt is always set to the comment character (#), to avoid accidental copy/paste mishaps. When bash sees ``` echo 'export PATH="/opt/local/bin:$PATH" >> ~/.profile ``` it does a several things. One is to expand the tilde (~) to the path of your home directory. Another is to recognize “echo” as a built-in command, and execute it. The command’s standard output is redirected (\>\>) to the end of the .profile, and echo’s command line arguments are exactly two: ``` echo export PATH="/opt/local/bin:$PATH" ``` Be careful not to mix up \>\> with a single \>, which would redirect echo’s standard output to overwrite the file entirely. The bash command: ``` export PATH="/opt/local/bin:$PATH" ``` prefixes “/opt/local/bin:” to the value of the PATH environment variable, and marks that variable as “exported” so its value will be inherited by subprocesses. The equivalent command in tcsh is: ``` setenv PATH "/opt/local/bin:$PATH" ``` The PATH variable holds a colon-separated list of directories to check for the programs you invoke. For example, when you type ruby, the shell should find /opt/local/bin/ruby. By contrast, if you were to type xeyes, the shell would check for /opt/local/bin/xeyes, but then have to keep looking through PATH (since xeyes lives in /usr/X11/bin). The point of setting PATH in ~/.profile is that bash reads .profile when you “log in.” Logging in, in this context, just means starting a new terminal. You also want to set it for the current shell, so you end up enter the export command twice: Once as an argument to echo > > ~/.profile, and again at the current shell’s prompt. When bash finds the location of a program, it may cache that location, to make future look-ups faster. If you change PATH, it’s a good idea to make bash throw away its cache, and look up program locations anew. The command to make bash discard its cache is ``` hash -r ``` The equivalent for tcsh is ``` rehash ``` > if I type in: echo ‘export PATH=“/opt/local/bin:$PATH”’ > > i get: export PATH=“/opt/local/bin:$PATH” on the terminal screen To the shell, double quotes (") mean “group these things into a single command-line argument, but expand any environment variables.” Single quotes (') perform the grouping, but also prevent expansion. You need single quotes for the echo to .profile, because you want $PATH to be expanded when the shell For example, given the following commands: ``` hello='What is up' echo $hello world echo "$hello world" echo '$hello world' ``` echo will be invoked three times, each with a different set of arguments. In the first case, the two arguments will be ‘What is up’ and ‘world’ (without the quotes). The double space will be lost, and echo will just print a single space between its arguments. In the second case, echo will receive the single argument ‘What is up world’ (without quotes), with the variable expanded and the double space preserved. In the third case, echo will receive the literal text ‘$hello world’ (again, no quotes), exactly as it was entered on the command line. > and when i type in: hash -r > the terminal says -r isn’t valid That’s a little odd. What happens when you type rehash? ---
**Author:** ![calvin](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/c/f475e1/32.png) [@calvin](https://www.ruby-forum.com/u/calvin)\ **Post date:** [May 19, 2009, 12:31am UTC](https://www.ruby-forum.com/t/beginner-ruby-question/168258/6 "2009-05-19T00:31:14Z")
On May 18, 2:13 pm, Jeff S. [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote: > > nothing happens > > your home directory. Another is to recognize “echo” as a built-in > The bash command: > for the programs you invoke. For example, when you type ruby, the shell > When bash finds the location of a program, it may cache that location, > > > if I type in: echo ‘export PATH=“/opt/local/bin:$PATH”’ > > (without quotes), with the variable expanded and the double space > preserved. In the third case, echo will receive the literal text > ‘$hello world’ (again, no quotes), exactly as it was entered on the > command line. > > > and when i type in: hash -r > > the terminal says -r isn’t valid > > That’s a little odd. What happens when you type rehash? Oh- I am using bash and i think the hash -r thing worked (i think) when i type in: which ruby1.9 I get /opt/local/bin/ruby1.9 and when I type ruby1.9 -v I get ruby 1.9.1p129 but if I just type in: which ruby I get /usr/bin/ruby and if I type ruby -v I get ruby 1.8.6 Thanks so much again for helping me out Jeff ---
**Author:** ![calvin](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/c/f475e1/32.png) [@calvin](https://www.ruby-forum.com/u/calvin)\ **Post date:** [May 19, 2009, 5:40am UTC](https://www.ruby-forum.com/t/beginner-ruby-question/168258/7 "2009-05-19T05:40:47Z")
Calvin wrote: > > > ~/.profile > > > > your home directory. Another is to recognize “echo” as a built-in > > The bash command: > > for the programs you invoke. For example, when you type ruby, the shell > > When bash finds the location of a program, it may cache that location, > > > > > if I type in: echo ‘export PATH=“/opt/local/bin:$PATH”’ > > > echo $hello world > > > ‘$hello world’ (again, no quotes), exactly as it was entered on the > > but > > if I just type in: which ruby I get /usr/bin/ruby > > and if I type ruby -v I get ruby 1.8.6 > > Thanks so much again for helping me out Jeff Do you have /opt/local/bin/ruby, or only /opt/local/bin/ruby1.9? To have port install ruby1.9 without the suffix, you have to pass the +nosuffix switch: ``` sudo port install ruby19 +nosuffix ``` Here’s the thread I followed when I was installing ruby 1.9 on OS X: [http://groups.google.com/group/rubyonrails-talk/browse\_thread/thread/0beb1ceb68a5ab3f](http://groups.google.com/group/rubyonrails-talk/browse_thread/thread/0beb1ceb68a5ab3f)