pemasu
OK testing SCREENSAVERPARAMS="s off dpms 0 0 0 -dpms" in pupx.
It didn't work out as I hoped. So...more digging, this time into the workings of xset. I hope it is somewhat useful....
#20921 <linuph>
How to use xset.
Xset is a tool to tweak X-server. There is lots of information to be found on the Internet. There are many questions and problems to be found too. Often the source of information is the same, incomplete, incorrect and confusing. After quite some looking up and trying I may have found the truth about xset.
Mind that there may be slightly different executions depending on the Linux kernel version and/or X-server version. This little piece was written for Puppy Linux Dpup Exprimo 5.X.3.4.2.12 with 3.4.2 kernel.
Xset has two distinct functions: screenblanking and powersaving including screenblanking. I deliberately use the word 'screenblanking' here to avoid a mixup with screensavers like xscreensaver, gnome-screensaver and others, even if xset uses the word 'screensaver' which is technically correct.
Xset came to the scene a long time ago when computers were equiped with CRT's and way before power saving (Energy Star, also technically know a DPMS or 'Display Power Management System') became a requirement.
Some DPMS functions therefore have no noticable effect with LCD screens. That is explained below.
If both functions are running screenblanking could kick in by either function or both. There is no visible difference: after all it's just screenblanking. So we have to correctly set the parameters of both functions to get what we want. Here is what I found so far:
# 1. Screenblanking xset s [options]
# xset s noblank : shows a large "X" when screen blanking kicks in
# xset s blank : will blank the screen only and not show the "X"
# xset s default : sets defaults timeout and cycle to 600 seconds and
blanking and exposure on
# xset s on : same as default
# xset s off : sets the timeout to zero = no screen blanking
# xset s expose : allows window re-exposures, i.e. redraws
# xset s noexpose : disables screenblanking unless the X server can
re-exposure (redraw)
# xset s activate : activates screenblanking immediately
# xset s reset : reset the screen after activate (to be used from a
shell)
# xset s [timeout] [cycle] : screen blanking kicks in after [timeout]
seconds. With 'blank' the screen simply blanks.
With 'noblank' set, an 'X' appears that varies in
size and position every [cycle] seconds.
At reboot blank is set, noexpose is set and cycle is set to 600. Other values remain as is.
# 2. DPMS power saving and screenblanking (Energy Star) *dpms, dpms [option]
# dpms [standby] : turns of the electron beam of a CRT after
[standby] seconds
# [suspend] : turns of the CRT monitor power supply
after [suspend] seconds
# [off] : turns of all power to the CRT monitor after [off]
seconds
The effect on a LCD montor is that screenblanking kicks in with either parameter larger than '0'. That is how it works with my monitor. Backlighting is then turned off in all cases. Other LCD's could recognize turning off of the backlighting (standby or suspend) seperately.
# If dpms is on (+dpms, see below), the lowest value except '0' will
kick off screenblanking.
Examples
xset dpms 0 0 5: kick off = 5
xset dpms 0 5 15: kick off= 5
xset dpms 15 5 5: kick off= 5
xset dpms 5 0 0: kick off = 5
# -dpms : turns dpms function off
# +dpms : turns dpms function on, dpms [standby[suspend[off]]] activated
# dpms force standby : blanks screen immediately
# dpms force suspend : same
# dpsm force off : same
# dpms force on : turns dpms on, same as +dpms
# Except for -dpms, all commands above turn DPMS on. If DPMS is on, xset q will show 'Monitor is on' meaning that DPMS is monitoring the system for user activity.
I think (hope) that the above is at least largely correct. I look forward to any comments.
ps I coudn't get the formatting quite correct....