postgresql-6.4.2/src/include/storage/s_lock.h contains:


#if defined(__alpha)
/*
 * OSF/1 (Alpha AXP)
 *
 * Note that slock_t on the Alpha AXP is msemaphore instead of char
 * (see storage/ipc.h).
 */
#define TAS(lock)	(msem_lock((lock), MSEM_IF_NOWAIT) < 0)
#define S_UNLOCK(lock)	msem_unlock((lock), 0)
#define S_INIT_LOCK(lock)	msem_init((lock), MSEM_UNLOCKED)
#define S_LOCK_FREE(lock)	(!(lock)->msem_state)
#endif	 /* __alpha */



#if defined(__sgi)
/*
 * SGI IRIX 5
 * slock_t is defined as a unsigned long. We use the standard SGI
 * mutex API. 
 *
 * The following comment is left for historical reasons, but is probably
 * not a good idea since the mutex ABI is supported.
 *
 * This stuff may be supplemented in the future with Masato Kataoka's MIPS-II
 * assembly from his NECEWS SVR4 port, but we probably ought to retain this
 * for the R3000 chips out there.
 */
#include <mutex.h>
#define TAS(lock)	(test_and_set(lock,1))
#define S_UNLOCK(lock)	(test_then_and(lock,0))
#define S_INIT_LOCK(lock)	(test_then_and(lock,0))
#define S_LOCK_FREE(lock)	(test_then_add(lock,0) == 0)
#endif	 /* __sgi */

#if defined(sinix)
/*
 * SINIX / Reliant UNIX 
 * slock_t is defined as a struct abilock_t, which has a single unsigned long
 * member. (Basically same as SGI)
 *
 */
#define TAS(lock)	(!acquire_lock(lock))
#define S_UNLOCK(lock)	release_lock(lock)
#define S_INIT_LOCK(lock)	init_lock(lock)
#define S_LOCK_FREE(lock)	(stat_lock(lock) == UNLOCKED)
#endif	 /* sinix */
 

#if defined(_AIX)
/*
 * AIX (POWER)
 *
 * Note that slock_t on POWER/POWER2/PowerPC is int instead of char
 * (see storage/ipc.h).
 */
#define TAS(lock)	cs((int *) (lock), 0, 1)
#endif	 /* _AIX */


#if defined (nextstep)
/*
 * NEXTSTEP (mach)
 * slock_t is defined as a struct mutex.
 */

#define S_LOCK(lock)	mutex_lock(lock)
#define S_UNLOCK(lock)	mutex_unlock(lock)
#define S_INIT_LOCK(lock)	mutex_init(lock)
/* For Mach, we have to delve inside the entrails of `struct mutex'.  Ick! */
#define S_LOCK_FREE(alock)	((alock)->lock == 0)
#endif	 /* nextstep */


-mochid