rem: Ns_MasterLock;
add: Ns_MasterLock();
context: Tcl_MutexLock(mutexPtr)    Tcl_Mutex *mutexPtr;	/* Really (Ns_Mutex **) */{    Ns_Mutex *nsmutexPtr = (Ns_Mutex *) mutexPtr;    if (*nsmutexPtr == NULL) {	Ns_MasterLock;	if (*nsmutexPtr == NULL) {	    static int next;	    char buf[20];	    sprintf(buf, "tcl:%d", next++);	    Ns_MutexInit(nsmutexPtr);	    Ns_MutexSetName(nsmutexPtr, buf);	}	Ns_MasterUnlock;    }    Ns_MutexLock(nsmutexPtr);}