pk stuff

Here’s a useful piece from David Lee on the Rails Oceania Google Group:

If any of you are using Ubuntu this is a pretty nice way to manage multiple ruby interpreters.

It has the advantage of managing the manpages, ri, and irb as “slaves”, so they change when a new interpreter is selected.

here’s the code:

# become root
su

# make sure the packages are installed for 1.8 & 1.9 aptitude install -s  ~n^ruby1.[89]$ ~n^irb1.[89]$ ~n^ri1.[89]

# install ruby1.8 & friends with priority 500
# so this will be the default “auto” choice
update-alternatives –install /usr/bin/ruby ruby /usr/bin/ruby1.8 500
–slave   /usr/share/man/man1/ruby.1.gz ruby.1.gz
/usr/share/man/man1/ruby.1.8.gz
–slave   /usr/bin/ri ri /usr/bin/ri1.8
–slave   /usr/bin/irb irb /usr/bin/irb1.8

# install ruby1.9 & friends with priority 400
update-alternatives –install /usr/bin/ruby ruby /usr/bin/ruby1.9 400
–slave   /usr/share/man/man1/ruby.1.gz ruby.1.gz
/usr/share/man/man1/ruby.1.9.gz
–slave   /usr/bin/ri ri /usr/bin/ri1.9
–slave   /usr/bin/irb irb /usr/bin/irb1.9

# choose your interpreter
# changes symlinks for /usr/bin/ruby ,
# /usr/bin/irb, /usr/bin/ri and man (1) ruby
update-alternatives –config ruby

for those with additional interpreters in say /usr/local/bin, other Debian variants, or managing other tools, vary as required.

% man update-alternatives

hope wrapping didn’t mangle it too much, and that someone finds this useful
…

Link to original here.