#include <fcntl.h> /* for struct flock */

typedef struct flock fileLock_t;
typedef fileLock_t *fileLock_p;

/* make a nice clean lock                                     */
fileLock_p makeLock(void);

/* obtains a write lock on the fd, returns the call to fcntl  */
int getLock(fileLock_p lock, int fd);

/* unlocks the write lock on fd,   returns the call to fcntl  */
int unLock(fileLock_p lock, int fd);

/* frees the lock made by a makeLock                          */
void freeLock(fileLock_p lock);