From c06b84d816fdeb6a26691b6f3504f541644edb6f Mon Sep 17 00:00:00 2001 From: Lennart Poettering Date: Fri, 12 Jul 2024 06:06:11 +0200 Subject: [PATCH] man: clarify what TTYReset= and TTYVTDisallocate= do and do not do regarding screen clearing --- man/systemd.exec.xml | 15 +++++++++------ 1 file changed, 9 insertions(+), 6 deletions(-) diff --git a/man/systemd.exec.xml b/man/systemd.exec.xml index 7a2fc76b656..c79cf674458 100644 --- a/man/systemd.exec.xml +++ b/man/systemd.exec.xml @@ -3322,7 +3322,8 @@ StandardInputData=V2XigLJyZSBubyBzdHJhbmdlcnMgdG8gbG92ZQpZb3Uga25vdyB0aGUgcnVsZX TTYReset= Reset the terminal device specified with TTYPath= before and after - execution. Defaults to no. + execution. This does not erase the screen (see TTYVTDisallocate= below for + that). Defaults to no. @@ -3333,11 +3334,12 @@ StandardInputData=V2XigLJyZSBubyBzdHJhbmdlcnMgdG8gbG92ZQpZb3Uga25vdyB0aGUgcnVsZX - TTYRows= TTYColumns= + TTYRows= Configure the size of the TTY specified with TTYPath=. If unset or - set to the empty string, the kernel default is used. + set to the empty string, it is attempted to retrieve the dimensions of the terminal screen via ANSI + sequences, and if that fails the kernel defaults (typically 80x24) are used. @@ -3345,9 +3347,10 @@ StandardInputData=V2XigLJyZSBubyBzdHJhbmdlcnMgdG8gbG92ZQpZb3Uga25vdyB0aGUgcnVsZX TTYVTDisallocate= - If the terminal device specified with TTYPath= is a virtual console - terminal, try to deallocate the TTY before and after execution. This ensures that the screen and scrollback - buffer is cleared. Defaults to no. + If the terminal device specified with TTYPath= is a virtual + console terminal, try to deallocate the TTY before and after execution. This ensures that the screen + and scrollback buffer is cleared. If the terminal device is of any other type of TTY an attempt is + made to clear the screen via ANSI sequences. Defaults to no. -- 2.47.3