no such command `shell'

[slayer]

    rbenv 0.2.1
    usage: rbenv <command> [<args>]

    Some useful rbenv commands are:
       commands      List all rbenv commands
       rehash        Rehash rbenv shims (run this after installing binaries)
       global        Set or show the global Ruby version
       local         Set or show the local directory-specific Ruby version
       shell         Set or show the shell-specific Ruby version
       version       Show the current Ruby version
       versions      List all Ruby versions known by rbenv
       which         Show the full path for the given Ruby command
       whence        List all Ruby versions with the given command

    See 'rbenv help <command>' for information on a specific command.
    For full documentation, see: https://github.com/sstephenson/rbenv#readme
    vlad@pant /tmp $ rbenv versions
      1.8.7-p352
      1.9.2-p290
    * ree-1.8.7-2011.03 (set by /home/vlad/.rbenv/version)
    vlad@pant /tmp $ rbenv shell 1.9.2-p290
    rbenv: no such command `shell'
    vlad@pant /tmp $ 

[josh]

This means you don't have rbenv init setup correctly.

# .bash_profile
eval "$(rbenv init -)"

[slayer]

sorry, I think my bash does not want to load profile:

vlad@pant ~ $ tail -3 ~/.bash_profile  
[ -x /usr/bin/keychain ] && /usr/bin/keychain 
export PATH="$HOME/.rbenv/bin:$PATH" 
eval "$(rbenv init -)" 
vlad@pant ~ $  
vlad@pant ~ $  
vlad@pant ~ $  
vlad@pant ~ $ rbenv shell 
rbenv: no such command `shell' 
vlad@pant ~ $  
vlad@pant ~ $ . ~/.bash_profile  
vlad@pant ~ $  
vlad@pant ~ $ rbenv shell 
rbenv: no shell-specific version configured 
vlad@pant ~ $  
vlad@pant ~ $  

[mlafeldt]

Seems like ~/.bash_profile is not sourced in your environment/OS. See #122 for discussion.

[kleinjm]

On zsh you may need to move eval "$(rbenv init -)" to .zshenv instead of .zshrc so rbenv is available in non-interactive shells.

[enextus]

I tried to use ~/.bashrc for my Ubuntu 20.04.
While file ~/.bash_profile LEFT EMPTY.
That works.