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POPthread passing arguments
 

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    <pre><code>char buff[MAX_SIZE]; int main() { pthread_t thread[3]; char message1 = 17; //17 = 0x11 char message2 = 18; char message3 = 19; char message4 = 20; int iret[3]; int k; char message[] = {17, 18,19,20}; /*THIS IS WORKING iret[0] = pthread_create( &amp;thread[0], NULL, write_to_buffer, (void*) &amp;message1); iret[1] = pthread_create( &amp;thread[1], NULL, write_to_buffer, (void*) &amp;message2); iret[2] = pthread_create( &amp;thread[2], NULL, write_to_buffer, (void*) &amp;message3); iret[3] = pthread_create( &amp;thread[3], NULL, write_to_buffer, (void*) &amp;message4); */ /* BUT THIS IS NOT iret[0] = pthread_create( &amp;thread[0], NULL, write_to_buffer, (void*) message); iret[1] = pthread_create( &amp;thread[1], NULL, write_to_buffer, (void*) (message+1)); iret[2] = pthread_create( &amp;thread[2], NULL, write_to_buffer, (void*) (message+2)); iret[3] = pthread_create( &amp;thread[3], NULL, write_to_buffer, (void*) (message+3)); */ for(k=0;k&lt;=3;k++) { pthread_join( thread[k], NULL); } //rest of main } void *write_to_buffer( void *ptr ) { while(1) { pthread_mutex_lock(&amp;my_mutex); char *message; message = (char *) ptr; //when passing by array I'm unable to get the value in the message variable printf("\nMeeee = %#x ", *(char*)ptr); //REST OF THE FUNCTION //logic to write to buffer pthread_mutex_unlock(&amp;my_mutex); //SOME LOGIC I OMMITED HERE //to return if(indexx &gt;= MAX_SIZE) return(NULL); } } </code></pre> <p>the problem i'm facing is that when i'm passing the array element i'm unable to capture the value in the thread function. but when i'm passing address of message1, message2, message3, and message4 i'm able to get the value passed in thread function </p>
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    1. USoomkiller
    1. USoomkiller
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    1. COTo start with, there's no need for the `(void*)` typecast, all pointers can be passed as `void*` without casting. To continue, what's the actual output of your code?
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      1. USSome programmer dude
    2. COWhat do you get when passing `message` (the 2nd case)?
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      1. USalk
    3. COBTW: There are 4 threads, but the array of threads is only 3 long.
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      1. USLostBoy
 

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