#include <pthread.h>
int pthread_join_np(pthread_t thread, void **status);
Threadsafe: Yes
Signal Safe: No

The pthread_join_np() function waits for a thread to terminate, then returns the threads exit status, while leaving the thread's data structures available for a later call to pthread_join(), pthread_join_np(), pthread_detach() or pthread_extendedjoin_np()

If the status parameter is NULL, the threads exit status is not returned.

The meaning of the threads exit status (value returned to the status memory location) is determined by the application except for the following conditions:

1. When the thread has been canceled using pthread_cancel(), the exit status of PTHREAD_CANCELED will be made available.
2. When the thread has been terminated as a result of an unhandled OS/400 exception, operator intervention or other proprietary OS/400 mechanism, the exit status of PTHREAD_EXCEPTION_NP will be made available.

This function is not portable

Parameters

thread

(Input) Pthread handle to the target thread

status

(Output) Address of the variable to receive the thread's exit status

None.

Return Value

0

pthread_join_np() was successful.

value

pthread_join_np() was not successful. value is set to indicate the error condition.

If pthread_join_np() was not successful, the error condition returned usually indicates one of the following errors. Under some conditions, the value returned could indicate an error other than those listed here.

[EINVAL]

The value specified for the argument is not correct.

[ESRCH]

The thread specified could not be found.

• The <pthread.h> header file. See Header files for Pthread functions
• pthread_detach()--Detach a Thread
• pthread_exit()--Terminate The Calling Thread
• pthread_extendedjoin_np()--Wait for a Thread with Extended Options
• pthread_join()--Wait for and Detach a Thread

#define _MULTI_THREADED
#include <pthread.h>
#include <stdio.h>
#include "check.h"

int  okStatus   = 12;

void *threadfunc(void *parm)
{
  printf("Inside secondary thread\n");
  return __VOID(okStatus);
}

int main(int argc, char **argv)
{
  pthread_t             thread;
  int                   rc=0;
  void                 *status;

  printf("Enter Testcase - %s\n", argv[0]);

  printf("Create thread using attributes that allow join\n");
  rc = pthread_create(&thread, NULL, threadfunc, NULL);
  checkResults("pthread_create()\n", rc);

  printf("Wait for the thread to exit\n");
  rc = pthread_join_np(thread, &status);
  checkResults("pthread_join_np()\n", rc);
  if (__INT(status) != okStatus) {
    printf("Secondary thread failed\n");
    exit(1);
  }

  printf("With pthread_join_np(), we can join repeatedly\n");
  rc = pthread_join_np(thread, &status);
  checkResults("pthread_join_np()\n", rc);
  if (__INT(status) != okStatus) {
    printf("Secondary thread failed\n");
    exit(1);
  }

  printf("Got secondary thread status as expected\n");
  /* Eventually, we should use pthread_join() or pthread_detach() */
  rc = pthread_detach(thread);
  checkResults("pthread_detach()\n", rc);
  
  printf("Main completed\n");
  return 0;
}

Enter Testcase - QP0WTEST/TPJOINN0
Create thread using attributes that allow join
Wait for the thread to exit
Inside secondary thread
With pthread_join_np(), we can join repeatedly
Got secondary thread status as expected
Main completed