Hello world example

The code can be downloaded from: hello.c:

#include <stdio.h>
#include <pvm3.h>

int main()
{
  int mytid;

  mytid = pvm_mytid();
  printf("My TID is %d\n", mytid);
  pvm_exit();
  return 0;
}

In order to compile the example issue the following command:

$ gcc -lpvm3 -o hello hello.c

And then run the hello program.

Master/slave

This is a simple PVM application, consisting of two processes ― master and slave ― communicating with each other.

The master

The code can be downloaded from: master.c:

#include <stdio.h>
#include <stdlib.h>
#include <pvm3.h>

int main()
{
  int myTID;
  int x = 12;
  int children[10];
  int res;

  myTID = pvm_mytid();
  printf("Master: TID is %d\n", myTID);

  res = pvm_spawn("slave", NULL, PvmTaskDefault, "", 1, children);
  if (res<1) {
    printf("Master: pvm_spawn error\n");
    pvm_exit();
    exit(1);
  }

  pvm_initsend(PvmDataDefault);
  pvm_pkint(&x, 1, 1);

  pvm_send(children[0], 1);

  pvm_recv(-1, -1);
  pvm_upkint(&x, 1, 1);

  printf("Master has received x=%d\n", x);

  pvm_exit();

  return 0;
}

The slave

The code can be downloaded from: slave.c:

#include <stdio.h>
#include <pvm3.h>

int main()
{
  int myTID, masterTID;
  int x = 12;

  myTID = pvm_mytid();
  printf("Slave: TID is %d\n", myTID);

  pvm_recv(-1, -1);
  pvm_upkint(&x, 1, 1);
  printf("Slave has received x=%d\n", x);

  sleep(3);
  x = x + 5;

  pvm_initsend(PvmDataDefault);
  pvm_pkint(&x, 1, 1);

  pvm_send(pvm_parent(), 1);

  pvm_exit();

  return 0;
}

Ring

The following ring.c example initializes communication in a ring of processes:

#include <stdio.h>
#include <pvm3.h>

#define PROC_NUM 3

int main()
{
  int myTID;
  int children[PROC_NUM];
  int res, i;

  myTID = pvm_mytid();
  printf("Master: TID is %d\n", myTID);

  res = pvm_spawn("ring-slave", NULL, PvmTaskDefault, "", PROC_NUM, children);
  if (res < 1)
  {
    printf("Master: pvm_spawn error (res=%d)\n", res);
    pvm_exit();
    exit(1);
  }

  // send neighbors' TIDs
  for(i=0; i<PROC_NUM; i++)
  {
    pvm_initsend(PvmDataDefault);
    pvm_pkint(&children[(i-1+PROC_NUM)%PROC_NUM], 1, 1);
    pvm_pkint(&children[(i+1)%PROC_NUM], 1, 1);
    pvm_send(children[i], 1);
  }

  // test the ring
  i=1;
  pvm_initsend(PvmDataDefault);
  pvm_pkint(&i, 1, 1);
  pvm_send(children[0], 1);

  pvm_exit();

  return 0;
}

The slave process is ring-slave.c:

#include <stdio.h>
#include <pvm3.h>

int main()
{
  int myTID, leftTID, rightTID, senderTID;
  int res, i, bufid;
  FILE* cons;

  cons = fopen("/dev/pts/2", "a");
  myTID = pvm_mytid();
  sleep(1);
  fprintf(cons, "\nSlave [%d]: started\n", myTID);

  // get neighbors' TIDs
  pvm_recv(-1, -1);
  pvm_upkint(&leftTID, 1, 1);
  pvm_upkint(&rightTID, 1, 1);

  fprintf(cons, "Slave [%d]: left=%d right=%d\n", myTID, leftTID, rightTID);
  sleep(1);

  while(1)
  {
    bufid = pvm_recv(-1, -1);
    pvm_upkint(&i, 1, 1);
    pvm_bufinfo(bufid, NULL, NULL, &senderTID);
    fprintf(cons, "Slave [%d]: msg %2d from %d\n", myTID, i, senderTID);
    sleep(1);
    i++;
    pvm_initsend(PvmDataDefault);
    pvm_pkint(&i, 1, 1);
    pvm_send(rightTID, 1);
    if (i>20) break;
  }

  pvm_exit();
  return 0;
}

Example configuration file (hostfile)

# comment line

lab-430-1.cs.put.poznan.pl
lab-430-2.cs.put.poznan.pl
lab-430-3.cs.put.poznan.pl

# different user and password
lab-430-13.cs.put.poznan.pl lo=user_pvm so=pw

# different pvmd path
lab-430-14.cs.put.poznan.pl dx=/bin/progs/pvm/pvmd

# different directory with executables
lab-430-15.cs.put.poznan.pl ep=$HOME/xxx/pvm3/bin/PVM_ARCH

# default option
* lo=std_user

lab-430-16.cs.put.poznan.pl
lab-430-17.cs.put.poznan.pl
lab-430-18.cs.put.poznan.pl

* lo=

# not in the initial configuration
&lab-430-4.cs.put.poznan.pl
&lab-430-5.cs.put.poznan.pl
&lab-430-6.cs.put.poznan.pl

PVM Examples