83 lines
1.8 KiB
C
83 lines
1.8 KiB
C
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#include <stdio.h>
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#include <stdlib.h>
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#include <time.h>
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#include <pthread.h>
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#include <unistd.h>
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#include <sys/types.h>
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#include <sys/ipc.h>
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#include <sys/sem.h>
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//~ HANDLE hEvent1, hEvent2;
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int key = 0x20; // Semaphore key
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int a[ 5 ];
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void Thread( void* pParams )
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{
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// Thread 2
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struct sembuf operation[1] ;
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// open semaphore
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int mysemid = semget(key, 2, 0);
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operation[0].sem_op = 1; // Release on the second resource
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operation[0].sem_num = 1;
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operation[0].sem_flg = SEM_UNDO;
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//Release semaphore 2
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semop(mysemid, operation, 1);
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int i, num = 0;
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while ( 1==1 )
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{
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WaitForSingleObject( hEvent2, INFINITE );
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for ( i = 0; i < 5; i++ ) a[ i ] = num;
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SetEvent( hEvent1 );
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num++;
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}
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}
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int main( void )
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{
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// Thread 1
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struct sembuf operation[2] ;
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// Create 2 semaphores
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semid = semget(key, 2, 0666 | IPC_CREAT);
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operation[0].sem_op = 1; //Release first resource
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operation[0].sem_num = 0;
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operation[0].sem_flg = SEM_UNDO;
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operation[0].sem_op = -1; // Wait on the second resource
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operation[0].sem_num = 1;
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operation[0].sem_flg = SEM_UNDO;
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//Release semaphore 1 and wait on semaphore 2
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// note : thread is suspended until the semaphore 2 is released.
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semop(semid, operation, 2);
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// thread is released
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// delete the semaphore
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semctl(semid, 0, IPC_RMID , 0)
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hEvent1 = CreateEvent( NULL, FALSE, TRUE, NULL );
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hEvent2 = CreateEvent( NULL, FALSE, FALSE, NULL );
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_beginthread( Thread, 0, NULL );
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while( 1==1 )
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{
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WaitForSingleObject( hEvent1, INFINITE );
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printf( "%d %d %d %d %d\n",
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a[ 0 ], a[ 1 ], a[ 2 ],
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a[ 3 ], a[ 4 ] );
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SetEvent( hEvent2 );
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}
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return 0;
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}
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