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#include <pmix.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
static void fence_collect(const char *nspace)
{
pmix_proc_t wildcard;
PMIx_Proc_load(&wildcard, nspace, PMIX_RANK_WILDCARD);
pmix_info_t info;
bool collect = true;
PMIx_Info_load(&info, PMIX_COLLECT_DATA, &collect, PMIX_BOOL);
PMIx_Fence(&wildcard, 1, &info, 1);
PMIx_Info_destruct(&info);
}
int main(int argc, char **argv)
{
(void)argc;
(void)argv;
pmix_proc_t me;
if (PMIx_Init(&me, NULL, 0) != PMIX_SUCCESS) {
fprintf(stderr, "PMIx_Init failed\n");
return 1;
}
printf("PMIx client initialized: nspace=%s rank=%u\n", me.nspace, me.rank);
const char *key = "mykey";
pmix_proc_t p0;
PMIx_Proc_load(&p0, me.nspace, 0);
// Round 0: Rank 0 puts "A"
if (me.rank == 0) {
pmix_value_t v;
PMIx_Value_load(&v, "A", PMIX_STRING);
PMIx_Put(PMIX_GLOBAL, key, &v);
PMIx_Commit();
PMIx_Value_destruct(&v);
printf("rank0: PUT 'A'\n");
}
fence_collect(me.nspace);
// Rank 1 reads and caches 'A'
if (me.rank == 1) {
pmix_value_t *out = NULL;
pmix_status_t rc = PMIx_Get(&p0, key, NULL, 0, &out);
printf("rank1: read1 -> rc=%d val=%s (now cached)\n",
rc, (out && out->type == PMIX_STRING) ? out->data.string : "NULL");
if (out) PMIx_Value_free(out, 1);
}
fence_collect(me.nspace);
// Round 1: Rank 0 overwrites with "B"
if (me.rank == 0) {
pmix_value_t v;
PMIx_Value_load(&v, "B", PMIX_STRING);
PMIx_Put(PMIX_GLOBAL, key, &v);
PMIx_Commit();
PMIx_Value_destruct(&v);
printf("rank0: PUT 'B' (overwrite)\n");
}
fence_collect(me.nspace);
// Rank 1: Try to get fresh value with REFRESH
if (me.rank == 1) {
pmix_info_t info[2];
bool refresh = true;
bool immediate = true;
PMIx_Info_load(&info[0], PMIX_GET_REFRESH_CACHE, &refresh, PMIX_BOOL);
PMIx_Info_load(&info[1], PMIX_IMMEDIATE, &immediate, PMIX_BOOL);
pmix_value_t *out = NULL;
pmix_status_t rc = PMIx_Get(&p0, key, info, 2, &out);
printf("rank1: read2 (REFRESH + IMMEDIATE) -> rc=%d val=%s (expect 'B')\n",
rc, (out && out->type == PMIX_STRING) ? out->data.string : "NULL");
if (out) PMIx_Value_free(out, 1);
PMIx_Info_destruct(&info[0]);
PMIx_Info_destruct(&info[1]);
}
PMIx_Finalize(NULL, 0);
return 0;
}
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