Kodexempel F14

/* Kolla alltid returvärden i riktig kod! */

#include <pthread.h> 
#include <stdio.h> 
 
void *printmsg(void *ptr) 
{ 
  puts((char *) ptr); 
}  
   
int main(void) 
{ 
  pthread_t thread1; 
  char *msg = "Hello, world!"; 
      
  pthread_create(&thread1, NULL, printmsg, msg);
  pthread_join(thread1, NULL); 

  return 0; 
} 



/* Funkar inte - varför? */ 
#include <pthread.h> 
#include <stdio.h> 
 
#define BUFSZ 1024 
 
pthread_mutex_t mtx1 = PTHREAD_MUTEX_INITIALIZER;
 
int sum=0; 
char buf[BUFSZ]; 
 
void *worker(void *ptr) 
{ 
    while (1) { 
        pthread_mutex_lock(&mtx1); 
        sum += atoi(buf); 
        pthread_mutex_unlock(&mtx1); 
    } 
}  
   
int main(void) 
{ 
    pthread_t thread1; 
    char *msg = "Hello, world!"; 
 
    pthread_create(&thread1, NULL, worker, msg);
     
    while (1) { 
        pthread_mutex_lock(&mtx1); 
        if (fgets(buf, BUFSZ, stdin)==NULL) 
            break; 
        pthread_mutex_unlock(&mtx1); 
    } 
    printf("Sum is %d\n", sum); 
    return 0; 
} 



/* Summera array. pthread.h, stdio.h */
 
#define NELEM 4096 
#define NTHR  16 
 
pthread_mutex_t mtx_sum; 
int arr[NELEM], sum=0; 
 
void *worker(void *arg) 
{ 
  int i, lsum=0, base_idx; 
 
  base_idx = (int) arg; 
  for (i=base_idx; i<base_idx+NELEM/NTHR; i++) 
    lsum+=arr[i]; 
     
  pthread_mutex_lock(&mtx_sum); 
  sum += lsum; 
  pthread_mutex_unlock(&mtx_sum); 
 
  return 0; 
}  
   
int main(void) 
{ 
  pthread_t trd[NTHR]; 
  int i; 
     
  pthread_mutex_init(&mtx_sum, NULL); 
  for (i=0; i<NELEM; i++) 
    arr[i]=i; 
 
  for (i=0; i<NTHR; i++)  
    pthread_create(&trd[i], NULL, worker, 
      (void *) (i*NELEM/NTHR));  
 
  for (i=0; i<NTHR; i++)  
    pthread_join(trd[i], NULL);

  printf("Sum is %d\n", sum); 
  return 0; 
} 



#include <pthread.h>

int pthread_create(pthread_t *new_thread_ID, const pthread_attr_t *attr,
  void *(*start_func)(void *), void *arg);

int pthread_join(pthread_t target_thread, void **status);

int pthread_mutex_lock(pthread_mutex_t *mp);
int pthread_mutex_unlock(pthread_mutex_t *mp);

int pthread_attr_init(pthread_attr_t *attr);
int pthread_attr_destroy(pthread_attr_t *attr);

int pthread_attr_setstacksize(pthread_attr_t *attr, size_t stacksize);
int pthread_attr_getstacksize(const pthread_attr_t *attr, size_t *stacksize);
/* m.fl m.fl... */



int isatty(int filedes); /* kolla om vi kör "direkt" eller med omdirigering */
char *ttyname(int filedes); /* kolla vart filedes "pekar" */



#include <stdio.h>
#include <stdlib.h>
#include <termios.h>
#include <unistd.h>

int main(int argc, char **argv)
{
        char c;
        struct termios buf, savebuf;

        tcgetattr(STDIN_FILENO, &savebuf);
        tcgetattr(STDIN_FILENO, &buf);
        buf.c_lflag &= ~(ICANON | ECHO);
        buf.c_cc[VMIN] = 0;
        buf.c_cc[VTIME] = (argv[1] != NULL) ? atoi(argv[1]) : 5;
        tcsetattr(STDIN_FILENO, TCSANOW, &buf);
        printf("Enter one character: ");
        fflush(stdout);
        if ((read(STDIN_FILENO, &c, 1)) != 1)
                printf("\nTimeout!\n");
        else
                printf("\nYou entered: %c.\n", c);
        tcsetattr (0, TCSAFLUSH, &savebuf);

        exit(0);
}