memsem.hh Source File

00001 /**********************************************************************
00002 * File: memsem.hh
00003 * Purpose: Provides function prototypes that let programmers
00004 * use a block of memory to implement a mutual exclusion semaphore.
00005 *
00006 * With LynxOs and SunOs using semop is very inefficient if the semaphore will
00007 * ussually be available. Other platforms may give you no semaphore operations.
00008 *************************************************************************/
00009 
00010 
00011 #ifndef MEMSEM_HH
00012 #define MEMSEM_HH
00013 
00014 #include "sem.hh"
00015 
00016 /* Take the mutual exclusion semaphore. */
00017 struct mem_access_object
00018 {
00019   void *data;
00020   long connection_number;
00021   long total_connections;
00022   double timeout;
00023   double sem_delay;
00024   int read_only;
00025   int split_buffer;
00026   char toggle_bit;
00027   RCS_SEMAPHORE *sem;
00028 };
00029 
00030 
00031 extern int mem_get_access (struct mem_access_object *mo);
00032 
00033 
00034 /* Give up the mutual exclusion semaphore. */
00035 extern int mem_release_access (struct mem_access_object *mo);
00036 
00037 #endif