All,
This may be a little off topic, but I though I would try here first.
I am writting a multi-threaded program and would like to have each
thread `managed' by a class. I have attempted to do this like this,
using the pthreads library:
<code>
====================begin cthread.h
class CThread
{
public:
CThread(void*);
~CThread();
....
private:
static CThread* m_pThis;
pthread_t m_tid;
static void* threadfun(void*);
....
}
==================== begin cthread.cpp
CThread* CThread::m_pThis = NULL;
CThread::CThread(void* arg)
{
int ret;
m_pThis = this;
if(0 != (ret = pthread_create(&m_tid, NULL, threadfun, arg)))
{
fprintf(stderr, "Thread creation failed");
}
}
void* threadfun(void* arg)
{
printf("Starting thread\n");
....
}
</code>
The code compiles without warnings or errors, except when I try and
run the application I get a segmentation fault at the pthread_create.
Trying to run under GDB, I am able to examine the value of the
variables and they seem consisten with what I would expect
// stop on the pthread_create line in the constructor...
(gdb) print m_pThis
$1 = (CThread*) 0xfee756b0
(gdb) print this
$2 = (CThread*0xfee756b0
(gdb) print m_tid
$3 = 134514818 // to be expected because I have not initialized
m_tid yet
(gdb) print &m_tid
$4 = (pthread_t*)0xfee756d8
(gdb) print threadfun
$5=&CThread::threadfun(void*)
// attempt the pthread_create line ....
Program received signal SIGSEGV, Segmenatation fault
0x0000000 in ?? ()
(gdb) where
#0 0x00000000 in ?? ( )
#1 0x0804a6bb in CThread (this=0xfee756b0, args=0x0) at ....
#2 0x08049aad in daemon_main(argc=3, argv=0xfeec42d4) at ....
#3 0x08049193 in main(argc=3, argv=0xfeec42d3) at main.cpp: 83
Any idea on what is going on, or how to fix?
Thanks,
George Huber
-
To unsubscribe from this list: send the line "unsubscribe linux-c-programming"
in
the body of a message to [EMAIL PROTECTED]
More majordomo info at http://vger.kernel.org/majordomo-info.html
