Have you ever wanted to write settings corresponding to OS types in tmux?

I use macOS and Linux(Ubuntu); the former is for my work and later is for a regular life. So I had a problem that cannot be shared with settings about clipboard in each OS.

However, the problem can be solved because if is introduced into tmux 2.4.

This will help us to write settings in each OS. It is true that we have not used else and elseif yet, but a pull request has been submitted to enable these operators.

Tmux if Syntax

In tmux, we can use if as %if. A sample has been public in tmux repository. Everyone can see the example.

%if supports == and != operator.

%if #{==,#{env_variable},expectation}
set foo
%endif
%if #{!=,#{env_variable},expectation}
set bar
%endif

My configuring .tmux.conf

I’m using Tmux v2.5.

% tmux -V
tmux 2.5

Tmux enables %if but the syntax is limited only environment variable now. It means that we must use variables which are defined as the variables.

I wrote settings on .tmux.conf like below:

%if #{==:#{OSTYPE},darwin16.0}
set-option -g status-right ‘SSID: #(get_ssid) | Battery: #(battery -c tmux) | [%Y-%m-%d %H:%M] | #H:[#P]’
bind-key -T copy-mode-vi Enter send-keys -X copy-pipe “reattach-to-user-namespace pbcopy”
bind-key -T copy-mode-vi y send-keys -X copy-pipe “reattach-to-user-namespace pbcopy”
set-option -g default-command “reattach-to-user-namespace -l $SHELL”
%end

%if #{==:#{OSTYPE},linux-gnu}
set-option -g status-right ‘[%Y-%m-%d %H:%M] | #H:[#P]’
bind-key -T copy-mode-vi Enter send -X copy-pipe-and-cancel “xsel -ip && xsel -op | xsel -ib”
bind-key -T copy-mode-vi y send -X copy-pipe-and-cancel “xsel -ip && xsel -op | xsel -ib”
%endif

And .zshrc:

% export OSTYPE=$OSTYPE

The reason why I wrote above is that OSTYPE has not been registered as environment variables. Furthermore, I could not use uname command becuase %if has supported for only environment variables. Also, I did not use * when I declared OS type in %if evaluation like darwin* and linux* because of not being supported *. Thus I set OSTYPE as an environment variable in loading .zshrc in order to distinguish Linux from macOS.