Definition:

#include <aMulti.tea>




void aMulti_Signal(

char proc, int data);

Parameters:

proc	-	The ID of the process that is awaiting data via a semaphore.
data	-	The data to be sent to the other process via a semaphore.

Return Value:

This routine does not return a value.

Description:

This routine sends data from one process to another via a semaphore.  The process that will receive the data must be expecting input via its semaphore.  The semaphore mechanism provides a means for synchronizing multiple processes.  Semaphores are accessed via ports.  The semaphore associated with a particular process is equal to the base address for semaphore ports plus the process ID.

Example:

(TEA file stored in file slot 0)
#include <aMulti.tea>

int main()
{
 int n;
 aMulti_Spawn(1,3);
 n=aMulti_Wait();
 aMulti_Signal(3,n);
 n=aMulti_Wait();
 aMulti_Signal(3,n);
 n=aMulti_Wait();
 return n;
}

(TEA file stored in file slot 1)
#include <aMulti.tea>

void main(char callingProcID)
{
 int n=100;
 aMulti_Signal(callingProcID,n);
 n=aMulti_Wait()+100;
 aMulti_Signal(callingProcID,n);
 n=aMulti_Wait()+100;
 aMulti_Signal(callingProcID,n);
}


The first program (0) runs the second program (1) as process 3.  The two processes take turns passing a value back and forth.  The value is increased by 100 on each round-trip.  Both processes terminate and the calling process returns the final value of 300.

Related:

aMulti_Spawn, aMulti_Kill, aMulti_Run00, aMulti_Run10, aMulti_Run11, aMulti_Run12, aMulti_Run13, aMulti_Halt, aMulti_Signal, aMulti_Wait, aPad_WriteInt, aPad_ReadInt, aPad_WriteChar, aPad_ReadChar