Programming

void test_queue()
{
struct mq_attr attr;

attr.mq_maxmsg = 10;
attr.mq_msgsize = 64;

mq_unlink("/my_test_queue");
if(mq_open("/my_test_queue", (O_RDWR + O_CREATE + O_EXCL), 0777, &attr) == -1)
{
  printf("\n__%s__errno(%d: %s)", __FUNCTION__, errno, strerror(errno));
  return FAIL;
}
}

(O_RDWR + O_CREATE + O_EXCL)

  00000001
+ 00000010
=========
  00000011

  00000011
+ 00000010
=========
  00000101

O_RDWR | O_CREATE | O_EXCL

/* foo.c */
#include <pthread.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

#include "foo.h" 

static pthread_t tid;

void* my_thread(void* ignore)
{
   int i;
   printf("Hello from thread\n");
   for (i=0; i<10; i++) {
      printf ("%d ", i); 
      fflush(stdout);
      sleep(1);
   }
}

void init(void)
{
   int rc;
   
   rc = pthread_create(&tid, NULL, my_thread, NULL);
   if (rc!=0) {
      fprintf(stderr,"pthread_create failed: %s (%d)\n", strerror(rc), rc);
      exit(1);
   }
}

/* foo.h */
#ifndef __FOO_H_
#define __FOO_H_
void init(void);
#endif

//myprog.c
#include <unistd.h>
#include "foo.h"

int
main()
{
   int val; 
   init();
   sleep(6);
}

cc -c foo.c
ar rcs libfoo.a foo.o
cc -pthread -static myprog.c -o myprog -L. -lfoo

Hello from thread
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