[Pkg-urxvt-maintainers] Bug#703884: Setting window title with ^]2; escape fails if sent too early

[Yuri D'Elia]

Package: rxvt-unicode-256color
Version: 9.15-2
Severity: minor

I'm using urxvt along with awesome-wm and zsh.
I have the following set into my .zshrc:

precmd() { print -Pn '\e]2;anything%~\a' }

which is pretty common and sets the window title to something before the
prompt is shown.

However, a good 30% of the times I get this when I start a new terminal:

precmd:print: write error: interrupt

as the first line in the buffer.

I tried to debug it with the zsh folks (to ensure that stdout is connected to
a tty, etc), but it seems that if the escape is sent too early it just fails,
whereas any other output does not cause problems. I can suppress the error,
but then of course the title is not set.

If I insert a small delay (0.1s) then it always works, which is "suspicious".