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Tech Arsenal 1
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Tech Arsenal (Arsenal Computer).ISO
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tek-04
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netprog.zip
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NETPROG.TAR
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lock
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locksem2.c
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C/C++ Source or Header
|
1989-12-17
|
407b
|
28 lines
/*
* Locking routines using simpler semaphore routines.
*/
#include <sys/types.h>
#include <sys/ipc.h>
#include <sys/sem.h>
#define SEMKEY 123456L /* key value for sem_create() */
int semid = -1; /* semaphore id */
my_lock(fd)
int fd;
{
if (semid < 0) {
if ( (semid = sem_create(SEMKEY, 1)) < 0)
err_sys("sem_create error");
}
sem_wait(semid);
}
my_unlock(fd)
int fd;
{
sem_signal(semid);
}