hal_init(3hal)

💖 hal_init — the "hi bestie, let's set up shop" function 💖

okay so real talk, this is hal_init from the HAL manual, section 3hal, and it's literally the first thing your module has to do before it's allowed to touch anything else. it's giving "hello world but make it realtime." ✨

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🎀 NAME 🎀

hal_init — Sets up HAL and RTAPI

🌸 SYNTAX 🌸

int hal_init(const char *modname)

🦋 ARGUMENTS 🦋

• modname — the name of this HAL module. that's it, that's the whole vibe, just your module's name bestie 💅

✨ DESCRIPTION ✨

so hal_init sets up HAL and RTAPI. no cap.

it must be called by any module that intends to use the API — and it has to happen before any other RTAPI calls, like, before anything. it's the main character of the setup phase, periodt. 👑

modname must point to a string that identifies the module. and here's the tea: that string may be no longer than HAL_NAME_LEN characters. don't be out here writing a novel in there, she has limits 🫶

🔥 REALTIME CONSIDERATIONS 🔥

🚨 call only from within non-realtime or init/cleanup code. do not call this from realtime tasks. like, do not. it's not the vibe, it's not the move, just don't. 💀

⭐ RETURN VALUE ⭐

• on success 💖 — returns a positive integer module ID. keep that thing safe, you'll need it for all your subsequent calls to the HAL and rtapi APIs. it's your little hall pass, your golden ticket, iykyk 🌈
• on failure 😭 — returns a HAL error code. not the slay, but at least she's honest about it.

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and that's the whole page bestie, we ate and left no crumbs 💅✨

big love to the LinuxCNC Documentation crew — this one's dated 2006-10-12, from the hal_init(3hal) era, and she's still iconic. 🎀 bye pookie, go init something 🦋