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Top Forums Programming Serial programming using termios Post 302781587 by jim mcnamara on Sunday 17th of March 2013 07:35:39 AM
Old 03-17-2013
First off, consider compiling with all warnings enabled. Example: void *read will trigger lots of problems. read, write are standard names for UNIX syscalls.

Next -
Code:
    pthread_create(&threads[0], NULL, write, NULL);
    pthread_create(&threads[1], NULL, read, NULL);
    pthread_exit(NULL);

means that as soon as the two threads are created (assuming they were since you do not check return codes), ALL threads will exit - when you call pthread_exit() from main() it shuts down everything. So if and why your code runs - I cannot see? check out pthread_join().

There are many other issues with your code. There is a concept in programming: 'not even wrong'. Code can be wrong for lots of reasons. But when code goes off into undefined behavior - which yours is doing - it then does not have actual meaning. No offense. Your write function is doing reads -getchar() is a read.

First step: turn on compiler warnings, example:
Code:
gcc -Wall myfile.c

Fix your code until there are ZERO warnings.

Check and obey your return codes.

After you get that organized, please come back with more questions.
 

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PTHREAD_CREATE(3)					   BSD Library Functions Manual 					 PTHREAD_CREATE(3)

NAME
pthread_create -- create a new thread LIBRARY
POSIX Threads Library (libpthread, -lpthread) SYNOPSIS
#include <pthread.h> int pthread_create(pthread_t *thread, const pthread_attr_t *attr, void *(*start_routine)(void *), void *arg); DESCRIPTION
The pthread_create() function is used to create a new thread, with attributes specified by attr, within a process. If attr is NULL, the default attributes are used. If the attributes specified by attr are modified later, the thread's attributes are not affected. Upon suc- cessful completion pthread_create() will store the ID of the created thread in the location specified by thread. The thread is created executing start_routine with arg as its sole argument. If the start_routine returns, the effect is as if there was an implicit call to pthread_exit() using the return value of start_routine as the exit status. Note that the thread in which main() was origi- nally invoked differs from this. When it returns from main(), the effect is as if there was an implicit call to exit() using the return value of main() as the exit status. The signal state of the new thread is initialized as: o The signal mask is inherited from the creating thread. o The set of signals pending for the new thread is empty. RETURN VALUES
If successful, the pthread_create() function will return zero. Otherwise an error number will be returned to indicate the error. ERRORS
The pthread_create() function will fail if: [EAGAIN] The system lacked the necessary resources to create another thread, or the system-imposed limit on the total number of threads in a process [PTHREAD_THREADS_MAX] would be exceeded. [EPERM] The caller does not have appropriate permission to set the required scheduling parameters or scheduling policy. [EINVAL] The value specified by attr is invalid. SEE ALSO
fork(2), pthread_attr(3), pthread_cancel(3), pthread_cleanup_pop(3), pthread_cleanup_push(3), pthread_exit(3), pthread_join(3) STANDARDS
The pthread_create() function conforms to ISO/IEC 9945-1:1996 (``POSIX.1''). BSD
March 15, 2014 BSD
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