text: #ifndef mutexModule_h
  #define mutexModule_h
  
  #include <stddef.h>
  #define MAX_MUTEX_ID 40
  
  void * mutexOpen(char id[MAX_MUTEX_ID]);
  
  void mutexClose(char id[MAX_MUTEX_ID]);
  
  void mutexLock(char id[MAX_MUTEX_ID]);
  
  void mutexUnlock(char id[MAX_MUTEX_ID]);
  
  #endif
  