I need to synchronise the threads with PPS (pulse per second) signal from GPS. Can somebody guide me.
I don’t know what the input from your GPS is. Maybe serial?
In any case the thread that wants to synchronize would wait in receive mode.
Before receiving with msg_receive() the thread would need to setup a connection and a channel.
From the same msg_receive() call it can wait for either QNX messages or pulses.
The thread that is reading the GPS input would trigger that pulse with Trigger(), waking up the waiting thread.
Pulses can have both an identifying number and a 32bit package. The package could indicate the time in some manner.