SNMP Subagent Programmer's Guide

Programming Tutorials
SNMP Subagent Programmer’s Guide—119728 2-31
Fault-Tolerant Hello World Program
/* Set up each agent environment */
living_agent_count = 0;
for (i=1; i<argc; i++) {
<-- 4
fprintf(stderr, "agent #%i is process %s\n", i, argv[i]);
/* Set up the management environment, registering ourselves as
* 1.3.6.1.4.1.442.2.1 with no password. */
if ((agent_info[i].mgmt_env = mgmt_init_env(argv[i],
<-- 5
(ObjId_t *) &GI_hello,
"Fault Tolerant Hello World Example",
(Octets_t *) NULL,
(void_function) NULL)) == NULL)
{
(void) fprintf(stderr, "%s: mgmt_init_env failure opening %s.\n",
argv[0], argv[i]);
return(2);
}
/* Let the agent know information what we're responsible for. */
if ((agent_info[i].mgmt_handle = w(agent_info[i].mgmt_env,
<-- 6
&SMI_GROUP_hello,
(void *)NULL)) == NULL)
{
(void) fprintf(stderr, "%s: mgmt_new_instance failure on #%i (%s)\n",
argv[0], i, argv[i]);
return(2);
}
/* allocate an IPC buffer: */
agent_info[i].mgmt_env->sess->agent_msg_buffer =
(char *) malloc (SNMP_MSG_MAX);
<-- 7
if (agent_info[i].mgmt_env->sess->agent_msg_buffer == NULL) {
(void) fprintf(stderr,
"%s: failure to malloc IPC buffer for agent #%\n", argv[0], i);
return(2);
}
/* start a READ on each agent */
agent_info[i].agent_filenumber = mgmt_read_nowait(
<-- 8
(struct mgmt_env *) agent_info[i].mgmt_env, NULL);
if (agent_info[i].agent_filenumber == -1) {
(void) fprintf(stderr, "%s: error from mgmt_read_nowait\n", argv[0]);
return(2);
}
living_agent_count++;
} /* end for */
/* main loop */
for(;;) {
<-- 9
wait:
if (living_agent_count < 1) {
(void) fprintf (stderr, "all agent processes died; I'm quitting too!\n");
exit(1);
} /* end if no agents */
event_fileno = -1;
status = AWAITIOX(&event_fileno,,&count_xferd,,100*helloPrintFreq); <--
10
if (status != CCE) {
FILE_GETINFO_(event_fileno, &error); <--
11
if (error == 40) { /* timeout! */
(void) fprintf (stderr,"%i second time out\n", helloPrintFreq);
(void) fputs((char *) helloText.val, stderr);
(void) fputs("\n", stderr);
helloPrintCnt++;
goto wait;
} else {
/* handle other errors here */
(void) fprintf(stderr, "AWAITIO error %i on file %i\n", error,
event_fileno);
for (i=1; i<argc; i++) {
if (event_fileno == agent_info[i].agent_filenumber) { <--
12
Example 2-4. Fault-Tolerant Hello World Program (page 2 of 3)