XSETDEVICEVALUATORS(3)

💅 XSETDEVICEVALUATORS(3) 💅

okay so bestie, welcome to XSetDeviceValuators from the XInput section of the manual (that's section 3, the library-calls girlies 💖). this is the one that goes and initializes the valuators on an extension input device. yes, we're doing hardware whisperer shit today. no cap.

---

✨ NAME ✨

XSetDeviceValuators — initialize the valuators on an extension input device 🎀

---

🌸 SYNOPSIS 🌸

#include <X11/extensions/XInput.h>

XSetDeviceValuators( Display *display,
                     XDevice *device,
                     int *valuators,
                     int first_valuator,
                     int num_valuators);

ok so here's what you're handing over, one by one 🫶

• display — the connection to the X server. like, your whole line to the server, your situationship with it 💜
• device — the device whose valuators are getting initialized. the main character of this whole function, honestly 👑
• valuators — a pointer to an array of integer values, and those values are what we're using to initialize the device's valuators 🍓
• first_valuator — the first valuator to be set. and listen, valuators are numbered starting at zero, not one. zero. periodt. ⭐
• num_valuators — how many valuators we're setting. the headcount, the guest list 💅

---

💖 DESCRIPTION 💖

the XSetDeviceValuators request sets the current values of the valuators of an input device. simple as that, bestie ✨

the valuators in the range first_valuator to (first_valuator + num_valuators) are set to the specified values. and once again for the people in the back: valuators are numbered beginning with 0 🔥

now here's the tea tho. not all input devices support initialization of valuator values. 😭 if you make this request to a device that does not support valuators initialization, you get a BadMatch error. not every device wants to be perceived, i guess.

if the request succeeds, a status of Success is returned 🎀 if another client has the device grabbed, a status of AlreadyGrabbed is returned. so if it's giving "someone else is holding it," that's exactly what's happening 💀

XSetDeviceValuators can generate a BadLength, BadDevice, BadMatch, or BadValue error.

---

🦋 DIAGNOSTICS 🦋

• BadDevice — an invalid device was specified. like, the specified device does not exist, or it has not been opened by this client via XOpenInputDevice. you can't talk to a device you never said hi to, bestie 🙈
• BadMatch — this error may occur if an XSetDeviceValuators request is made specifying a device that has no valuators and reports no axes of motion, or if such a request is made specifying a device that does not support valuator initialization. lowkey the vibe check failed 💅
• BadValue — an invalid first_valuator or num_valuators value was specified. numbers were given that simply cannot be given, and honestly? rude 😭

ngl, read the BadMatch one twice. "no valuators and reports no axes of motion" and "does not support valuator initialization" are both real, both possible, and both will absolutely end your whole afternoon. 🌈

---

that's the page, bestie. go forth and initialize responsibly 🧚💜

XSetDeviceValuators(3) — from the XInput crew, dated 05/18/2026. mwah, take care of her 💅✨