Add flag to delay shell launch until after window initialization

[kchibisov]

Linux
Wayland

If you start vim with alacritty -e vim it's size will be incorrect most of the time. You can fix it with resize event though. The issue is presented on both evlp2 and master branches. Can be workaround by inserting std::thread::sleep_ms(100) in the beginning of the handle_resize.

Broken vim looks like this.

[osimplex]

This behavior I can reproduce on Linux with X11.

I can also reproduce this with URxvt, using the command:
urxvt -e vim ~/.config/alacritty/alacritty.yml
The problem is less prone to occur if I do:
alacritty -e sleep 0.1 ; vim ~/.config/alacritty/alacritty.yml
Or, on URxvt:
urxvt -e sh -c "sleep 0.1 ; vim ~/.config/alacritty/alacritty.yml"

Bigger the, more prone to fail.

This problem, I think, is on Vim. The Qtile project have a reference for this kind of problem occuring on Xterm, URxvt and Rxvt.
Xterm have a flag -wf that can be used in such situation, when the program cannot handle 'inicializing' terminal state. Terminal should "wait for the window to be mapped the first time before starting the subprocess" (man xterm).

[osimplex]

Can I reproduce this bug with Neovim too. alacritty -e nvim.
A little different of Vim, Neovim is smaller than terminal window, and, as in bug report, after resize Neovim fits in terminal window and works as expected.

These programs, Vim an Neovim, expect that the terminal window will only call them after the terminal window is properly mapped.

[chrisduerr]

Yeah, this isn't an Alacritty bug, but instead an issue with applications running inside of Alacritty without handling size changes.

So a flag like XTerm's -wf is required.

[Chaitanyabsprip]

I am still facing this issue, any resolve?

[hisham-maged10]

hey I've found a fix for the issue, from my understanding it's an issue related to vim/neovim, it needs a certain signal to be sent from the terminal on start
adding this to your vim config file ~/.vimrc
autocmd VimEnter * :silent exec "!kill -s SIGWINCH $PPID"
fixes it