JOINGROUP(3PVM)

💖 NAME 💖

pvm_joingroup — the little routine that enrolls the calling process in a named group, bestie. That's it. That's the whole vibe. ✨

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🦋 SYNOPSIS 🦋

C girlies:

int inum = pvm_joingroup( char *group )

Fortran girlies:

call pvmfjoingroup( group, inum )

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🌸 PARAMETERS 🌸

• group — a character string, aka the group name of an existing group. Not a hypothetical group. Not a group you're manifesting. An existing one. 👑
• inum — the integer instance number that gets returned by the routine. Instance numbers start at 0 and count up, like a lil counter that only goes one way. And if you see a value less than zero? That's an error, bestie. Not a personality trait. 💀

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✨ DESCRIPTION ✨

Okay so pvm_joingroup enrolls the calling task into the group named group, and hands you back the instance number inum of this task inside this group. That's the whole plot. 🎀

And if something goes wrong? inum will be negative. No cap. Negative = error, always.

Instance numbers start at 0 and count up. When you're using groups, a (group, inum) pair uniquely identifies a PVM process — that's the whole point of the pairing, iykyk. This is consistent with the PVM 2.4 naming schemes, so it's not new-new, it's legacy-consistent, which is honestly kind of iconic. 👑

Now here's the tea: if a task leaves a group by calling pvm_lvgroup and then later rejoins the same group, the task is not guaranteed to get the same instance number. Read that again. Not. Guaranteed. 🫠 PVM attempts to reuse old instance numbers, so when a task joins a group it'll get the lowest available instance number. So basically PVM is doing its best to give you your old seat back, but it's a vibe, not a promise. 💅

And the best part? A task can be a member of multiple groups simultaneously. Multitasking queen behavior. Main character energy fr fr. 🌈

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🍓 EXAMPLES 🍓

C:

inum = pvm_joingroup( "worker" );

Fortran:

CALL PVMFJOINGROUP( 'group2', INUM )

Look at that. Two languages, one dream. 🫶

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💀 ERRORS 💀

These error conditions can be returned by pvm_joingroup, and yes, you will be hearing about all of them:

• PvmSysErr — pvmd was not started or has crashed. RIP the daemon, nothing is happening until that's sorted. 😭
• PvmBadParam — giving a NULL group name. Bestie. You gotta give it a name. 🙈
• PvmDupGroup — trying to join a group you are already in. Girl. You're literally already there. 💅

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🎀 SEE ALSO 🎀

• pvm_lvgroup(3PVM) — the leaving-the-group counterpart, for when you need to exit the chat. 👋

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And that's the page!! This was PVM Version 3.4, dated 30 August, 1993 — yes, she's an elder, and yes, she still ate. 💜✨ Stay grouped, stay iconic, mwah 🎀🦋