# Slurmctld Generic Plugin Programmer Guide

## Overview

This document describes slurmctld daemon's generic plugins and the API that defines them. It is intended as a resource to programmers wishing to write their own slurmctld generic plugins. This is version 100 of the API.

The slurmctld generic plugin must conform to the Slurm Plugin API with the following specifications:

const char plugin_name[]="full text name"

A free-formatted ASCII text string that identifies the plugin.

const char plugin_type[]="major/minor"

The major type must be "slurmctld_plugstack." The minor type can be any suitable name for the type of slurmctld package. Slurm can be configured to use multiple slurmctld_plugstack plugins if desired.

## API Functions

int init (void)

Description:
Called when the plugin is loaded, before any other functions are called. Put global initialization here.

Returns:
SLURM_SUCCESS on success, or
SLURM_ERROR on failure.

void fini (void)

Description:
Called when the plugin is removed. Clear any allocated storage here.

Returns: None.

Note: These init and fini functions are not the same as those described in the dlopen (3) system library. The C run-time system co-opts those symbols for its own initialization. The system _init() is called before the SLURM init(), and the SLURM fini() is called before the system's _fini().

Only the init and fini functions of the plugin will be called. The init function will be called when the slurmctld daemon begins accepting RPCs. The fini function will be called when the slurmctld daemon stops accepting RPCs. In the case of the backup slurmctld daemon, the init and fini functions may be called multiple times (when it assumes control functions and then when it reliquishes them to the primary slurmctld daemon).

## Versioning

This document describes version 100 of the Slurm Job Submission API. Future releases of Slurm may revise this API.

Last modified 8 May 2014