Berkeley CSUA MOTD:Entry 19972
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2025/07/10 [General] UID:1000 Activity:popular
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2000/12/1 [Computer/SW/Languages] UID:19972 Activity:nil
11/30   I'm having a problem running a toy pthreads program on FreeBSD. I ran
        strace on it and it looks like it exits after SIGUSR1 or SIGUSR2. The
        same program seems to run fine on (dare I say it) Linux. Any ideas?

#include <stdio.h>
#include <pthread.h>

void print_msg( void *ptr ) {
char *message;
message = (char *) ptr;
printf("%s ", message);
}

int main(int argc, char **argv) {

pthread_t thread1, thread2;
char *message1 = "Hello";
char *message2 = "World";

pthread_create(&thread1, NULL, (void*)&print_msg, (void*) message1);
pthread_create(&thread2, NULL, (void*)&print_msg, (void*) message2);

return 0;
}
        \_ Insert after the creates:

           pthread_join(thread1, NULL);
           pthread_join(thread2, NULL);

           I have no idea what I'm doing. -clueless-sodan
           \_ Yep, you definitely to somehow block so that the threads
              have time to execute.  Otherwise main() will just
              exit; whether or not it waits for threads to run to
              termination is implementation dependent.
              \_ Yeah, I just figured out that this is true. I guess
                 this is one other aspect where LinSUX tries to act
                 smart for you. The annoying thing is that I copied
                 the example right out of the pthreads book from Sun.
                 The Sun Press authors generally don't leave this sort
                 of thing out. (Yes the book is on pthreads, not solaris
                 threads).
        \_ Build with gcc -pthread?
           \_ I compiled with cc -g -Wall -pthread -o thread_test thread_test.c
              the two print_msg functions never get called.
              \_ Please follow the clueless-sodan's advice. -clueless-sodan
2025/07/10 [General] UID:1000 Activity:popular
7/10    

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