iTerm2 is probably the reason I stick to developing in OS X instead of switching to a moderately saner alternative. It’s a brilliant terminal emulator with tonnes of nifty features—none of which I’m willing to give up!

A minor example is inline italics fonts. Compare editing in Markdown in vim-pandoc with italics:

vim italics

and without:

vim sans-italics

Due to fun terminfo settings, my $TERM setting of choice—xterm-256color—does not claim to have codes to turn on and off italics. Other posts have suggested creating a copy that extends xterm-256color and setting iTerm’s $TERM variable appropriately. I disagree.

The problem is when SSHing into machines without your custom terminfo entry installed—other machines don’t know what to do with it. They resort to safe defaults which means everything gets screwy. In order to get around it, you have to make sure to add an appopriate line to your remote .bash_profile, .zshrc or the similar file that sets your $TERM to xterm-256color or at least something compatible, lest you suffer losing all of your pretty visual features in Vim. To me, this is unacceptable.

My solution

Simply override the local entry for xterm-256color! Sure, it’s a bit uncouth, but you’re only affecting your own machine, right? The worst that can happen is that remote machines won’t display italics. Conversely, you probably don’t SSH into your Mac, so the fact that you have a “damaged” terminfo entry is entirely irrelevant. If you’re still with me, do the following:

Write the installed terminfo entry to a temporary text file using infocmp:

infocmp xterm-256color > /tmp/xterm-256color.terminfo

Then, append the magic line sitm=\E[3m, ritm=\E[23m, which defines the escape codes that iTerm will interpret to render things in pretty italics:

printf '\tsitm=\\E[3m, ritm=\\E[23m,\n' >> /tmp/xterm-256color.terminfo

And now overwrite the existing terminfo entry for xterm-256color:

tic /tmp/xterm-256color.terminfo

Now open a new terminal and type the following to test:

echo `tput sitm`italics`tput ritm`

Here are all the steps combined in one dangerously copy-pastable snippet:

infocmp xterm-256color > /tmp/xterm-256color.terminfo
printf '\tsitm=\\E[3m, ritm=\\E[23m,\n' >> /tmp/xterm-256color.terminfo
tic /tmp/xterm-256color.terminfo


If you upgrade OS X (say from Mavericks to Yosemite), you will have to do this all over again. Because Apple isn’t too keen with you administering your own system. ¯\_(ツ)_/¯