Does Dream.run clobber terminal line wrapping setting, and depend on TERM=xterm-256color?

[aantron]

Dream.run, if not called with adjust_terminal:false, sets some terminal settings, and then tries to restore them on exit (code below).

• We have switched to Ctrl+C for exit. Are the settings being restored during exit by Ctrl+C? This can be checked by inserting a print_endline into the restore_terminal function, and just making sure the print occurs.
• @thangngoc89 reported Dream messing with the terminal somehow inside tmux, where TERM wasn't originally xterm-256color. Is the way Dream is changing the settings portable across terminal emulation modes?

In the future, either the log will be terminal width-aware, or we will probably just use dumb line wrapping, and always behave as if adjust_terminal:false at the Dream.run level.

dream/src/http/http.ml

Lines 818 to 838 in b8a46f4

	let adjust_terminal =
	adjust_terminal && Sys.os_type <> "Win32" && Unix.(isatty stderr) in
	let restore_terminal =
	if adjust_terminal then begin
	(* The mystery terminal escape sequence is $(tput rmam). Prefer this,
	hopefully it is portable enough. Calling tput seems like a security
	risk, and I am not aware of an API for doing this programmatically. *)
	prerr_string "\x1b[?7l";
	flush stderr;
	let attributes = Unix.(tcgetattr stderr) in
	attributes.c_echo <- false;
	Unix.(tcsetattr stderr TCSANOW) attributes;
	fun () ->
	(* The escape sequence is $(tput smam). *)
	prerr_string "\x1b[?7h";
	flush stderr
	end
	else
	ignore
	in

[outkine]

restore_terminal was not being called on Ctrl+C, but it does with this PR.

[aantron]

I think the first part of this issue was fixed in #151. I'm not observing any issues with tmux at the moment.