/*   Shaun Cooper
     September 26, 2000

     Simple thread example to demonstrate how a thread is invoked.

     Note:  You must compile this code with certain flags

                    gcc file.c -lpthread


    Relevant manual pages (via google) are:
       pthread
       pthread_create
      pthread_join


*/


#include <pthread.h>
#include <errno.h>


/*  define a structure so that we can provide 2 values to the
    function (thread)
*/

typedef struct {int val1, val2;} input;


/* simple function which outputs the values of the structures 4 times */

void f( input * j )
{
  int i;

  
  for(i=0;i<=4;i++)
   {  printf ("in f, val1 is %d and val2 is %d\n",(*j).val1,(*j).val2);
   }

}



/* simple example of a thread call */
main()
{ int i;
  int j;

  input in;

  pthread_t t_child1;
  int status1;

  in.val1=20;
  in.val2=30;

  /* this creates a thread by calling the function "f".
     The input to f really is 2 values, so we pack them into
     a structure and provide a pointer to the stricture */

  if ((j=pthread_create(&t_child1,NULL,(void *)f,&in)) != 0 )
     {
       printf("Cannot create thread %d\n",j);
       exit(1);
     }

  /* this waits on the thread to finish */
  pthread_join(t_child1,(void **) &status1);



}