linux下用C语言写的聊天程序！/*BUG and NOTE: Not join protect to Shared Memory Segments,example Semaphore Arrays. Not check the parameters validity. When transmit may be error. If the client program no right exit,others cannot know,the service program shouldbe check the client program whether exist timing. The program when exit(), it do not delete the Shared Memory Segments,you maybe use atexit() but the program have some processes. When one process is exit(),others is continue. The service program s action is few. And so on. */
