JOINGROUP(3PVM)

💖 NAME 💖

pvm_joingroup — the glow-up moment where the calling process gets enrolled in a named group ✨ like joining a group chat but make it distributed computing 🫶

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🌸 SYNOPSIS 🌸

C

int inum = pvm_joingroup( char *group )

Fortran

call pvmfjoingroup( group, inum )

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🎀 PARAMETERS 🎀

• group — a character string, bestie. It's the group name of an existing group. Not a vibe you're manifesting, an actual existing one 💅
• inum — the integer instance number the routine hands back to you. Instance numbers start at 0 and count up 📈. Any value less than zero? That's an error, no cap 😭

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🦋 DESCRIPTION 🦋

Okay so here's the tea ☕ — pvm_joingroup enrolls the calling task in the group named group, and returns the instance number inum of this task within that group. And if something goes wrong? inum goes negative. That's it, that's the drama 🙈

Instance numbers start at 0 and count up, periodt. When you're using groups, a (group, inum) pair uniquely identifies a PVM process — which is consistent with the PVM 2.4 naming schemes, iconic behavior honestly 👑

Now here's the part you need to know 👀: if a task leaves a group by calling pvm_lvgroup and later rejoins that same group, the task is not guaranteed to get the same instance number back. PVM attempts to reuse old instance numbers, so when a task joins a group it gets the lowest available instance number. So like, it tries, but don't come for it if it doesn't 💀

And the slay part? A task can be a member of multiple groups simultaneously. Multitasking queen energy, we love to see it 🌈

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✨ EXAMPLES ✨

C:

inum = pvm_joingroup( "worker" );

Fortran:

CALL PVMFJOINGROUP( 'group2', INUM )

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💀 ERRORS 💀

These error conditions can be returned by pvm_joingroup, and we're listing every single one because transparency is self-care 🫶

• PvmSysErr — pvmd was not started or has crashed 😭 the whole thing said "not today"
• PvmBadParam — you gave a NULL group name. Bestie. You have to actually name the group 💅
• PvmDupGroup — trying to join a group you are already in. Ma'am, you're already there 😭

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👑 SEE ALSO 👑

pvm_lvgroup(3PVM) — the exit strategy, iykyk 🚪✨

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Okay that's the whole page, and I'm obsessed with you for reading it 💜 This was JOINGROUP(3PVM) from PVM Version 3.4, dated 30 August, 1993 — yes bestie, 1993, ancient but still ate 🌸 Now go join your group and get that low instance number, fr fr 🎀