DMXChangeS...Attributes(3)

✨ DMXChangeS...Attributes(3) ✨

okay bestie, so this one's from the Library Functions Manual and it's literally called DMXChangeScreensAttributes 💅 let's get into it

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💖 NAME 💖

DMXChangeScreensAttributes — change back-end screen attributes

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🌸 SYNOPSIS 🌸

#include <X11/extensions/dmxext.h>

int DMXChangeScreensAttributes(Display *dpy,
                               int screen_count,
                               int *screens,
                               int mask_count,
                               unsigned int *masks,
                               DMXScreenAttributes *attr,
                               int *error_screen);

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🦋 DESCRIPTION 🦋

so basically, DMXChangeScreensAttributes() is the glow-up function 💅 it changes the geometries and positions of the DMX screen and DMX root windows over on the back-end X servers. like, you're rearranging the whole vibe.

• screen_count tells you how many screens are getting changed, periodt.
• for each screen: the screen number goes in screens, an attribute mask goes in masks, and a DMXScreenAttributes structure goes in attr. three little slots, one per screen, no cap.

oh and if you want the full explanation of the DMXScreenAttributes structure? it's all in DMXGetScreenAttributes(3) — go read that one, bestie, it ate 🫶

🌈 the mask values 🌈

the values used to compute each entry in masks are these, exactly:

• DMXScreenWindowWidth
• DMXScreenWindowHeight
• DMXScreenWindowXoffset
• DMXScreenWindowYoffset
• DMXRootWindowWidth
• DMXRootWindowHeight
• DMXRootWindowXoffset
• DMXRootWindowYoffset
• DMXRootWindowXorigin
• DMXRootWindowYorigin

🎀 the mask_count shortcut 🎀

ngl, in general mask_count should just be equal to screen_count. that's the standard, that's the moment.

but — as a little convenience — mask_count can be less than screen_count, and then the last entry in masks gets reused for all the remaining screens. it's giving "one mask, many screens" ✨ and it means you can make identical changes across several screens using just one mask. iconic behavior honestly.

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🔥 RETURN VALUE 🔥

on success, 0 is returned. slay. 🎉

otherwise, error_screen gets set to the value of the first screen in the list that caused the error, and a non-zero value comes back at you.

• if screen_count or mask_count is less than 1, or if any of the attribute values are not within the appropriate bounding boxes → DmxBadValue is returned 💀
• if a protocol error happens → DmxBadReply is returned 🙈

also, DMXChangeScreensAttributes() can generate BadLength (if the data you provided does not match the data implicitly required by the screen_count and mask_count values), BadValue (if the values in screens are not valid), and BadAlloc errors. so like... be careful out there 💀

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💜 SEE ALSO 💜

• DMXGetScreenCount(3)
• DMXGetScreenAttributes(3)
• DMX(3)
• Xdmx(1)

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and that's the whole page, bestie!! 🫶 this one came to you from X Version 11, libdmx 1.1.5, and it lives in the Library Functions Manual as DMXChangeS...Attributes(3). mwah 💋 go change some screens, you main character 👑