From 2bff41d1f67a757962c7f1db5223ee676d10e7f5 Mon Sep 17 00:00:00 2001 From: Peter Stephenson Date: Thu, 4 Sep 2014 09:31:44 +0100 Subject: 33091: improve documentation for ttyctl --- Doc/Zsh/builtins.yo | 18 +++++++++++++++--- 1 file changed, 15 insertions(+), 3 deletions(-) (limited to 'Doc') diff --git a/Doc/Zsh/builtins.yo b/Doc/Zsh/builtins.yo index f709f5020..9862c637e 100644 --- a/Doc/Zsh/builtins.yo +++ b/Doc/Zsh/builtins.yo @@ -1639,14 +1639,26 @@ Do nothing and return an exit status of 0. findex(ttyctl) cindex(tty, freezing) item(tt(ttyctl) tt(-fu))( -The tt(-f) option freezes the tty, and tt(-u) unfreezes it. +The tt(-f) option freezes the tty (i.e. terminal or terminal emulator), and +tt(-u) unfreezes it. When the tty is frozen, no changes made to the tty settings by external programs will be honored by the shell, except for changes in the size of the screen; the shell will simply reset the settings to their previous values as soon as each command exits or is suspended. Thus, tt(stty) and similar programs have -no effect when the tty is frozen. Without options it reports whether the -terminal is frozen or not. +no effect when the tty is frozen. Freezing the tty does not cause +the current state to be remembered: instead, it causes future changes +to the state to be blocked. + +Without options it reports whether the terminal is frozen or not. + +Note that, regardless of whether the tty is frozen or not, the +shell needs to change the settings when the line editor starts, so +unfreezing the tty does not guarantee settings made on the +command line are preserved. Strings of commands run between +editing the command line will see a consistent tty state. +See also the shell variable tt(STTY) for a means of initialising +the tty before running external commands. ) findex(type) item(tt(type) [ tt(-wfpams) ] var(name) ...)( -- cgit 1.4.1