The VideoLAN Forums

Hi,
Why do I see two threads involved in opening file when I stop on breakpoint in static int Open( vlc_object_t * p_this ) function? (at /vlc/modules/demux/mp4/mp4.c)

Hi, why do you assume both threads are for opening the file ?

try "thread apply all backtrace" to see what each thread is doing.

because I see 2 thread stack on left pane and cursor jump from one to another from step to step. "thread apply all backtrace" doesn't change the behaviour.

"thread apply all backtrace" doesn't change a behaviour, it displays the current callstack of each thread.

I can't really know what your left pane is or what you're doing though.

ok. You can add line
"fprintf( stderr, "static int Open in thread %lu\n", vlc_thread_id () );"
to the "static int Open( vlc_object_t * p_this )" function in /vlc/modules/demux/mp4/mp4.c file.
Run and see the output:
"
static int Open in thread 5489
static int Open in thread 5488
"
My question is: why the player opens the file twice?

One time is for preparsing, the second time is for actually playing it.