[9fans] Re:Q about screenshots

[9fans] Re:Q about screenshots

[a.b]

>And just exactly what happens if the cp occurs while >the screen is in the
>middle of an update.
>Does it grab the old frame, wait for the new frame to >complete, or just
>give you a gibberish dump of the interim buffer >contents which are almost
>certainly worthless?

I don't know it exactly, nevertheless I think the
display is locked when redraw is in process.
So, cp /dev/screen blbla should wait.

Sasa.

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Re: [9fans] Re:Q about screenshots

[mirtchov]

> I don't know it exactly, nevertheless I think the
> display is locked when redraw is in process.
> So, cp /dev/screen blbla should wait.

no, you get an image beginning with the first screen and ending with
the updated one -- try it with some of the faster xscr programs, it
almost always occurs..

you can get display locking (man lockdisplay) however most programs
don't use it

Re: [9fans] Re:Q about screenshots

[Charles Forsyth]

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i think that's locking for processes sharing the display
data structures within a shared address space, not locking the
display itself, and indeed that's what {man lockdisplay}
seems to describe!

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From: mirtchov@cpsc.ucalgary.ca
To: 9fans@cse.psu.edu
Subject: Re: [9fans] Re:Q about screenshots
Date: Tue, 7 Oct 2003 07:40:28 -0600
Message-ID: <38d954a5d27b3145900d481a32aca753@plan9.ucalgary.ca>


> I don't know it exactly, nevertheless I think the
> display is locked when redraw is in process.
> So, cp /dev/screen blbla should wait.

no, you get an image beginning with the first screen and ending with
the updated one -- try it with some of the faster xscr programs, it
almost always occurs..

you can get display locking (man lockdisplay) however most programs
don't use it