obtenir une erreur dans le programme c "référence indéfinie à gettid"

C'est mon thread sous-routine...
Ici, je suis la création de 4 threads et en passant de la structure comme un argument pour enfiler des sous-routine.

Je suis en train d'imprimer l'id de thread avec getid() fonction,

Je suis d'erreur disant "undefined reference to gettid()".

J'ai ajouté les fichiers d'en-tête nécessaires...

#include <pthread.h>
#include <stdio.h>
#include <sys/types.h>
#define ARRAYSIZE 17
#define NUMTHREADS 4
struct ThreadData {
int start, stop;
int* array; 
};
void* squarer(void* td) 
{
struct ThreadData* data=(struct ThreadData*) td;
int start=data->start;
int stop=data->stop;
int* array=data->array;
int i;
pid_t tid1;
tid1 = gettid(); //error at this statement//`
printf("tid : %d\n",tid1);
for (i=start; i<stop; i++) {
sleep(1);
array[i]=i*i;
printf("arr[%d] = [%d]\n",i,array[i]);
} 
return NULL;
}
int main(void) {
int array[ARRAYSIZE];
pthread_t thread[NUMTHREADS];
struct ThreadData data[NUMTHREADS];
int i;
int tasksPerThread=(ARRAYSIZE+NUMTHREADS-1)/NUMTHREADS;
for (i=0; i<NUMTHREADS; i++) {
data[i].start=i*tasksPerThread;
data[i].stop=(i+1)*tasksPerThread;
data[i].array=array;
}
data[NUMTHREADS-1].stop=ARRAYSIZE;
for (i=0; i<NUMTHREADS; i++) {
pthread_create(&thread[i], NULL, squarer, &data[i]);
}
for (i=0; i<NUMTHREADS; i++) {
pthread_join(thread[i], NULL);
}
for (i=0; i<ARRAYSIZE; i++) {
printf("%d ", array[i]);
}
printf("\n");
return 0;
}

source d'informationauteur PravinY

  1. 19

    Essayer

    #include <unistd.h>
#include <sys/syscall.h>
#ifdef SYS_gettid
pid_t tid = syscall(SYS_gettid);
#else
#error "SYS_gettid unavailable on this system"
#endif
  2. 1

    J'ai suivi les suggestions fournies sur errro et corrigé la source
    *ci-dessous est l'erreur de code libre * 

    #include <pthread.h>
#include <stdio.h>
#include <sys/types.h>
#include <unistd.h>
#include <sys/syscall.h>
#define ARRAYSIZE 17
#define NUMTHREADS 4
struct ThreadData {
int start, stop;
int* array; 
};
void* squarer(void* td) 
{
struct ThreadData* data=(struct ThreadData*) td;
int start=data->start;
int stop=data->stop;
int* array=data->array;
int i;
pid_t tid1;
tid1 = syscall(SYS_gettid); //here is the correct statement //
printf("tid : %d\n",tid1);
for (i=start; i<stop; i++) {
sleep(1);
array[i]=i*i;
printf("arr[%d] = [%d]\n",i,array[i]);
} 
return NULL;
}
int main(void) {
int array[ARRAYSIZE];
pthread_t thread[NUMTHREADS];
struct ThreadData data[NUMTHREADS];
int i;
int tasksPerThread=(ARRAYSIZE+NUMTHREADS-1)/NUMTHREADS;
for (i=0; i<NUMTHREADS; i++) {
data[i].start=i*tasksPerThread;
data[i].stop=(i+1)*tasksPerThread;
data[i].array=array;
}
data[NUMTHREADS-1].stop=ARRAYSIZE;
for (i=0; i<NUMTHREADS; i++) {
pthread_create(&thread[i], NULL, squarer, &data[i]);
}
for (i=0; i<NUMTHREADS; i++) {
pthread_join(thread[i], NULL);
}
for (i=0; i<ARRAYSIZE; i++) {
printf("%d ", array[i]);
}
printf("\n");
return 0;
}