/* This program has NUMBER_OF_PROCS processes executing the same 
   function (MyJob()) at the same time, on the same shared 
   variable (SharedCounter). Each process increments the variable  
   a MAX_COUNT number of times.

   Runs on SGI machines runnning IRIX 5.3 (not sure about others).

   Compile:	cc share.c -o share
	where share.c if the name of this file and share will be
	the name of the executable.
   
   Run:		share
	at the prompt (the prompt is most likely % if you have 
	a C or a C like shell, or $ if you have one of the other
	shells).
  
*/

#include <ulocks.h>
#include <task.h>
#include <sys/types.h>
#include <stdio.h>

#define errprint(S)	fprintf(stderr, "*** %s\n", S);

#define NUMBER_OF_PROCS	2
#define MAX_COUNT	1000000
#define MAX_TRIES	1000


/* data visisble by all processes that will be spawn.
*/
int SharedCounter=0;

 
/* Here goes the code that will be concurently executed by processes.
   MyJob() increments the SharedCounter global variable a MAX_COUNT
   number of times.
*/

void MyJob()
{
int i;

    for (i=0; i<MAX_COUNT; i++) {
        SharedCounter++;
    }
}


/* In main() set the number of processes that will be used, by
   calling m_set_procs(), then do the actual process creation
   by calling m_fork(). At the end kill the child processes with
   m_kill_procs().
*/

main()
{
int ret_status;

    ret_status = m_set_procs(NUMBER_OF_PROCS);
    if (ret_status != 0) {
	errprint("m_set_procs() failed");
	exit(1);
    }
    ret_status = m_fork(MyJob);
    if (ret_status != 0) {
	errprint("m_fork() failed");
	exit(2);
    }
    m_kill_procs();
    printf("SharedCounter = %d\n", SharedCounter);
}