MPI_T_CVAR_READ(3)

💅 MPI_T_cvar_read — bestie, let's read a control variable ✨

okay so this is the Open MPI manual page for MPI_T_cvar_read (section 3 of the manual, iykyk), and it's genuinely one of the simpler ones — like, the vibe is "reach into the MPI Tools interface and grab the current value of a control variable." main character energy, honestly 🎀

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🌸 SYNTAX 🌸

C Syntax

#include <mpi.h>

int MPI_T_cvar_read(MPI_T_cvar_handle handle, const void *buf)

that's it. that's the whole signature. she's cute, she's compact, she slays 💅

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🦋 INPUT PARAMETERS 🦋

• handle — the handle of the control variable you wanna read. like the little VIP pass that identifies which control variable we're talking about 🎟️
• buf — the initial address of the storage location for the variable value. yes bestie, you bring the storage, this function just fills it in 🫶

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✨ DESCRIPTION ✨

so MPI_T_cvar_read reads the value of the control variable identified by the handle you pass in, and stores that value in the buffer pointed to by buf. simple, iconic, no cap 💖

but listen — the caller must ensure that the buffer pointed to by buf is large enough to hold the entire value of the control variable. that's a you problem, not a her problem. she will happily write the whole value in there, so if your buffer is too smol, that's on you 😭 size it right, periodt.

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💀 ERRORS 💀

MPI_T_cvar_read will fail if:

• MPI_T_ERR_NOT_INITIALIZED — the MPI Tools interface is not initialized. like, you can't read the vibes before the vibes have been set up, bestie 🙈
• MPI_T_ERR_INVALID_HANDLE — the handle is invalid. fake ID, no entry, blocked at the door 💅

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👀 SEE ALSO: 👀

• MPI_T_cvar_handle_alloc
• MPI_T_cvar_get_info

go read those too, they're the supporting cast and they ate 🔥

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👑 COPYRIGHT 👑

2003-2026, The Open MPI Community

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aaaand that's the page! 🎀 this lil gem comes to you courtesy of the Open MPI crew, dated Sep 11, 2026 — mwah, go read some control variables, love u, bye 🦋💜