enable italic font on tmux

tmux_italic.md

based on https://www.reddit.com/r/vim/comments/24g8r8/italics_in_terminal_vim_and_tmux/

• Check if italic font is supported:

$ echo -e "\e[3mitalic\e[23m"

• Also check:

$ infocmp $TERM | grep sitm
        sgr0=\E(B\E[m, sitm=\E[3m, smacs=\E(0, smam=\E[?7h,
$ infocmp $TERM | grep ritm
        ri=\EM, rin=\E[%p1%dT, ritm=\E[23m, rmacs=\E(B,

If nothing is returned, then here is the step to enable it:

1. Create a the file screen-256color.terminfo with the following content:

# A screen-256color based TERMINFO that adds the escape sequences for italic.
#
# Install:
#
#   tic screen-256color.terminfo
#
# Usage:
#
#   export TERM=screen-256color
#
screen-256color|screen with 256 colors and italic,
        sitm=\E[3m, ritm=\E[23m,
        use=screen-256color,

2. Execute the command:

$ tic screen-256color.terminfo

3. Add the following lines to .vimrc:

set t_ZH=^[[3m
set t_ZR=^[[23m

NOTE: ^[ must be entered with <C-V><Esc> 3. Add the following line to .tmux.conf:

set -g default-terminal "screen-256color"

NOTE: It the step 3 does not work, start tmux using the following command:

$ env TERM=screen-256color tmux