PMIX_INIT(3)

💖 PMIX_INIT(3) — the OpenPMIx glow-up 💖

okay bestie, sit down, hydrate, and let me tell you about PMIx_Init — literally the first thing your PMIx client ever does. it's giving "hello world but make it parallel." ✨

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🌸 NAME 🌸

PMIx_Init — Initialize the PMIx Client

like, the whole entire point is: wake up the PMIx client. that's it. that's the post. 💅

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✨ SYNOPSIS ✨

#include <pmix.h>

pmix_status_t PMIx_Init(pmix_proc_t *proc);

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🎀 ARGUMENTS 🎀

• proc — a pointer to a pmix_proc_t object, and this is where the client's namespace and rank get dropped off on the way back out. it's basically the little basket the server hands your identity back in. 🧺

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🦋 DESCRIPTION 🦋

So. You're initializing the PMIx client, and the function hands you back the process identifier that this client's application got assigned, all cozy inside that pmix_proc_t struct you passed in. 🫶

Now here's the lil plot twist: passing NULL for proc is totally allowed — the original says so, no cap — if you only want to initialize the PMIx system and genuinely don't need the identifier back at that exact moment. sometimes you just want the vibes, not the receipt. 💁

When you call it, the PMIx client goes looking for the connection info it needs from the local PMIx server, and then it establishes the connection. and if that info is nowhere to be found? or the server connection straight-up fails? then an appropriate error constant comes back at you. not a cute moment but an honest one. 😭

If it is successful, the function returns PMIX_SUCCESS and fills your provided structure with the server-assigned namespace and rank of the process within the application. main character assignment confirmed. 👑

Also super important: the PMIx client library is reference counted, so multiple calls to PMIx_Init are allowed. Which means — plot twist — one totally valid way to get the namespace and rank of your process is to just call PMIx_Init with a non-NULL parameter. iconic behavior. 🔥

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💜 RETURN VALUE 💜

Returns PMIX_SUCCESS on success. On error, it returns a negative value corresponding to a PMIx errno. that's your sign fr fr. ⭐

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🌈 ERRORS 🌈

PMIx errno values are defined in pmix_common.h. go look there, she's got the full list. 🙈

See also:

• PMIx_Initialized(3)
• PMIx_Abort(3) <#man3-pmix-abort>
• PMIx_Commit(3)
• PMIx_Finalize(3) <#man3-pmix-finalize>
• PMIx_Put(3)
• pmiAddInstance(3)
• pmiAddMetric(3)

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👑 COPYRIGHT 👑

Copyright 2014-2026, OpenPMIx Community

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and that's the whole page, bestie — go forth and initialize. periodt. 💖✨🎀

this page is from the OpenPMIx manual, dated Aug 04, 2026 — shoutout to the OpenPMIx crew for keeping the docs alive, ily 🫶🌈