MPI_T_CVAR_GET_NUM(3)

💖 MPI_T_CVAR_GET_NUM(3) 💖

okay bestie, so we're deep in the Open MPI man pages rn and this one is literally about asking the MPI Tools interface "hey girl, how many control variables do we have rn?" That's it. That's the whole vibe. MPI_T_cvar_get_num — Query the number of control variables. Iconic behavior, no notes. 🎀

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✨ SYNTAX ✨

C Syntax

#include <mpi.h>

int MPI_T_cvar_get_num(int *num_cvar)

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🫶 OUTPUT PARAMETERS 🫶

• num_cvar — this is where the current number of control variables gets dropped off for you. she's the answer slot, treat her nice. 💅

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🌸 DESCRIPTION 🌸

okay so MPI_T_cvar_get_num is your girl for querying the current number of control variables. that's the whole job. she counts, you receive. 🧚

and here's the tea that actually matters — the number of control variables may increase as your process keeps executing, but it will never decrease. ever. it only goes up, like your screen time. so don't be out here assuming the number you got earlier is still the number now, but also don't ever stress about it shrinking, because it fr fr won't. ⭐

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💀 ERRORS 💀

MPI_T_cvar_get_num will fail if:

• MPI_T_ERR_NOT_INITIALIZED — the MPI Tools interface isn't initialized yet 💔 like girl you have to set it up first, we can't do anything until you do, that's the rule, periodt.

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🚨 reminder bestie: that error is a real one, not a vibe. if the MPI Tools interface not initialized, you get MPI_T_ERR_NOT_INITIALIZED and nothing else. init first, then query. iykyk. 🫶

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Copyright: 2003-2026, The Open MPI Community 🎀

so yeah, that's the whole page — brought to you by Open MPI, dated Sep 10, 2026, and the copyright belongs to The Open MPI Community spanning 2003-2026. mwah, go query something. 💜✨