Example code for https://github.com/pmix/pmix-standard/pull/276

Chap_Examples.tex

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% Chapter: Examples
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\chapter{Examples}
\label{chap:examples}

This chapter contains various code examples that \ac{PMIx} users may find helpful.


%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\section{Example C Code}

Example block of C code
\begin{pmixCodeC}
int main() {
    printf("Hello World!\n");
    return 0;
}
\end{pmixCodeC}

The inline code \pmixCodeInlineC{printf("Hello World");} prints ``Hello World''.

Example of a selection of a file:
\pmixCodeImportC[firstline=72, lastline=84]{sources/hello.c}%

Example with highlighting:
\pmixCodeImportC[firstline=72, lastline=84, highlightlines={2-5,7}]{sources/hello.c}%


%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\section{Example C Code from Preprocessor}

Example of a selection of a file:
\pmixCodeImportC{sources/_autogen_/hello-alt.c_pmix_init}%

Example with highlighting:
\pmixCodeImportC[highlightlines={4,7,14-15}]{sources/_autogen_/hello-alt.c_pmix_get}%

Another example
\pmixCodeImportC{sources/_autogen_/hello-alt.c_pmix_init}%

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\section{Example Python Code from Preprocessor}

The inline code \pmixCodeInlinePy{print("Hello World")} prints ``Hello World''.

Another example
\pmixCodeImportPy{sources/_autogen_/hello.py_pmix_init}%

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\section{Synchronizing Fence}
\label{chap:examples:syncfence}

This example shows how to call a synchronizing \refapi{PMIx_Fence} operation across the entire namespace.
To signify the entire namespace we are using the \refconst{PMIX_RANK_WILDCARD} constant.

\pmixCodeImportC[firstline=72, lastline=84, highlightlines={2-5,7}]{sources/hello.c}%

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

hello-alt.c

/*
 * Copyright (c) 2004-2010 The Trustees of Indiana University and Indiana
 *                         University Research and Technology
 *                         Corporation.  All rights reserved.
 * Copyright (c) 2004-2011 The University of Tennessee and The University
 *                         of Tennessee Research Foundation.  All rights
 *                         reserved.
 * Copyright (c) 2004-2005 High Performance Computing Center Stuttgart,
 *                         University of Stuttgart.  All rights reserved.
 * Copyright (c) 2004-2005 The Regents of the University of California.
 *                         All rights reserved.
 * Copyright (c) 2006-2013 Los Alamos National Security, LLC.
 *                         All rights reserved.
 * Copyright (c) 2009-2012 Cisco Systems, Inc.  All rights reserved.
 * Copyright (c) 2011      Oak Ridge National Labs.  All rights reserved.
 * Copyright (c) 2013-2018 Intel, Inc. All rights reserved.
 * Copyright (c) 2015      Mellanox Technologies, Inc.  All rights reserved.
 * Copyright (c) 2020      IBM Corporation.  All rights reserved.
 * $COPYRIGHT$
 *
 * Additional copyrights may follow
 *
 * $HEADER$
 *
 */

#define _GNU_SOURCE
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <time.h>
#include <ctype.h>

#include <pmix.h>

int main(int argc, char **argv)
{
    //<EG BEGIN ID="pmix_init">
    //<EG BEGIN ID="pmix_get">
    pmix_status_t rc = PMIX_SUCCESS;
    pmix_proc_t myproc;
    //<EG END ID="pmix_init">
    pmix_value_t *val;
    uint16_t localrank;
    //<EG END ID="pmix_get">

    //<EG BEGIN ID="pmix_init">
    rc = PMIx_Init(&myproc, NULL, 0);
    if (PMIX_SUCCESS != rc) {
        return 1;
    }
    //<EG END ID="pmix_init">

    //<EG BEGIN ID="pmix_get">
    /* Get our rank local to this node */
    rc = PMIx_Get(&myproc, PMIX_LOCAL_RANK, NULL, 0, &val);
    if (PMIX_SUCCESS != rc) {
        return 2;
    }
    localrank = val->data.uint16;
    PMIX_VALUE_RELEASE(val);
    //<EG END ID="pmix_get">

    /* Fence to hold all processes in this namespace */
    pmix_proc_t wildproc;
    PMIX_PROC_CONSTRUCT(&wildproc);
    (void)strncpy(wildproc.nspace, myproc.nspace, PMIX_MAX_NSLEN);
    wildproc.rank = PMIX_RANK_WILDCARD;

    rc = PMIx_Fence(&wildproc, 1, NULL, 0);
    if (PMIX_SUCCESS != rc) {
        fprintf(stderr,
                "Client ns %s rank %d: PMIx_Fence failed: %s\n",
                myproc.nspace, myproc.rank, PMIx_Error_string(rc));
        goto done;
    }

  done:
    /* Finalize the PMIx library */
    printf("Client ns %s rank %d: Finalizing\n", myproc.nspace, myproc.rank);
    rc = PMIx_Finalize(NULL, 0);
    if (PMIX_SUCCESS != rc) {
        fprintf(stderr, "Client ns %s rank %d:PMIx_Finalize failed: %s\n",
                myproc.nspace, myproc.rank, PMIx_Error_string(rc));
    } else {
        printf("Client ns %s rank %d:PMIx_Finalize successfully completed\n",
               myproc.nspace, myproc.rank);
    }

    return rc;
}