Yes... thats right.
But gettid() and pthread_self() should return the same value according to me.
Can anyone correct me or confirm my theory?
I don't have access to a Linux-box right now, otherwise I would have
tested this theory.
My Linux box is Fedora Core 5, whose pthread library is NPTL.
In my test, the gettid() != pthread_self(). I think the id returned
by pthread_self() is assigned by pthread library.But I am not
sure. My test is shown as follow.
#include <stdio.h>
#include <pthread.h>
#include <sys/types.h>
#include <linux/unistd.h>
#include <errno.h>
_syscall0(pid_t, gettid);
void* func (void* argc)
{
int i = *((int*)argc);
printf("In the thread %d:posix tid %u\n", i, pthread_self());
printf("In the thread %d:pid %u\n", i, getpid());
printf("In the thread %d:tid %u\n", i, gettid());
}
int main()
{
pthread_t th[2];
int i, ret;
printf("main posix tid: %u\n", pthread_self());
printf("main pid: %u\n", getpid());
printf("main tid: %u\n", gettid());
for (i = 0; i < 2; i++)
ret = pthread_create (&th[i], NULL, func, (void*)&i);
for (i = 0; i < 2; i++)
pthread_join (th[i], NULL);
return 0;
}
--------------------results----------------------------------------
main posix tid:3086476976
main pid: 14700
main tid: 14700
In the thread 0:posix tid 3086474144
In the thread 0:pid 14700
In the thread 0:tid 14701
In the thread 1:posix tid 3075984288
In the thread 1:pid 14700
In the thread 1:tid 14702
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