/* include my_lock_init */ #include "unpthread.h"## 1 ##src/server/lock_pthread.c## #include ## 2 ##src/server/lock_pthread.c## static pthread_mutex_t *mptr; /* actual mutex will be in shared memory */## 3 ##src/server/lock_pthread.c## void## 4 ##src/server/lock_pthread.c## my_lock_init(char *pathname)## 5 ##src/server/lock_pthread.c## {## 6 ##src/server/lock_pthread.c## int fd;## 7 ##src/server/lock_pthread.c## pthread_mutexattr_t mattr;## 8 ##src/server/lock_pthread.c## fd = Open("/dev/zero", O_RDWR, 0);## 9 ##src/server/lock_pthread.c## mptr = Mmap(0, sizeof(pthread_mutex_t), PROT_READ | PROT_WRITE,## 10 ##src/server/lock_pthread.c## MAP_SHARED, fd, 0);## 11 ##src/server/lock_pthread.c## Close(fd);## 12 ##src/server/lock_pthread.c## Pthread_mutexattr_init(&mattr);## 13 ##src/server/lock_pthread.c## Pthread_mutexattr_setpshared(&mattr, PTHREAD_PROCESS_SHARED);## 14 ##src/server/lock_pthread.c## Pthread_mutex_init(mptr, &mattr);## 15 ##src/server/lock_pthread.c## }## 16 ##src/server/lock_pthread.c## /* end my_lock_init */ /* include my_lock_wait */ void## 17 ##src/server/lock_pthread.c## my_lock_wait()## 18 ##src/server/lock_pthread.c## {## 19 ##src/server/lock_pthread.c## Pthread_mutex_lock(mptr);## 20 ##src/server/lock_pthread.c## }## 21 ##src/server/lock_pthread.c## void## 22 ##src/server/lock_pthread.c## my_lock_release()## 23 ##src/server/lock_pthread.c## {## 24 ##src/server/lock_pthread.c## Pthread_mutex_unlock(mptr);## 25 ##src/server/lock_pthread.c## }## 26 ##src/server/lock_pthread.c## /* end my_lock_wait */