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PThreads: question on basic problem (or POSIX Threads)

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Join Date: Oct 2004

Posts: 31

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jaeSun

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PThreads: question on basic problem (or POSIX Threads)

Oct 22nd, 2004

ok, I have an assignment ...

it requires the use of pthreads ..

i pretty much understand it, well, sorta ....

the assignment is to read input from the command line (input redirection) from a file

the file contains a list of numbers, 1 per line, 50 total numbers max

we are then going to sort the numbers using the Odd-Even Transposition Sorting Algorithm.

so for each number we compare and sort, we are to use pthreads for each set of 2 numbers ...

anyone familiar with the sorting algorithm?

if not, let me know, and ill explain, but otherwise, ill default to the guess that you guys do ...

anyways ....

my question is, with pthreads, you have to create a PThread ID for each pthread call, right?

example:

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main()
{
     pthread_t thread1, thread2;
     char *message1 = "Thread 1";
     char *message2 = "Thread 2";
     int  iret1, iret2;
 
    /* Create independant threads each of which will execute function */
 
     pthread_create( &thread1, NULL, print_message_function, (void*) message1);
     pthread_create( &thread2, NULL, print_message_function, (void*) message2);
.
.
.
.
.
main()
{
     pthread_t thread1, thread2;
     char *message1 = "Thread 1";
     char *message2 = "Thread 2";
     int  iret1, iret2;

    /* Create independant threads each of which will execute function */

     pthread_create( &thread1, NULL, print_message_function, (void*) message1);
     pthread_create( &thread2, NULL, print_message_function, (void*) message2);
.
.
.
.
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we declared 2 pthread ID's, "thread1" and "thread2"

this allowed me to create 2 different threads?

but in my assignment, we dont know how many threads we will be creating until we read in all the numbers ....

so im not sure how to declare all the pthread ID's I will need to declare?

any help/point-in-right-direction would be great .....