47 lines
1.0 KiB
C
47 lines
1.0 KiB
C
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#include <stdio.h>
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#include <stdlib.h>
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#include <sys/types.h>
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#include <sys/ipc.h>
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#include <sys/shm.h>
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#include "info.h"
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int main()
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{
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int id;
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struct info *ctrl;
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id = shmget( KEY,MSIZ, 0 );
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// get the id of the already created shared memory segment
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// .. function to create is same as getting id of the already created shared memory segment
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if ( id < 0 )
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{
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//error … ;
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exit(1) ;
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}
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// attach a local pointer to the shared memory
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ctrl = (struct info *) shmat( id, 0, 0);
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if ( ctrl <= (struct info *) (0) )
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{
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//error … ;
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exit(1) ;
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}
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while (ctrl->flag!=-1)
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{
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// if flag is 1, add the numbers from shared memory, set flag to 0
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if (ctrl->flag==1)
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{
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ctrl->sum = ctrl->value1+ctrl->value2;
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printf("Sum: %f + %f = %f\n", ctrl->value1, ctrl->value2, ctrl->sum);
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ctrl->flag = 0;
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}
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}
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//detach the pointer from the shared memory
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// .. we do not need to delete here, can be done in either of the process
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shmdt(ctrl);
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exit(0);
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}
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