IPC研究（7） -- IPC Status Commands

爲了system V IPC的完整性，加上兩個有用的shell command: ipcs 和 ipcrm
chenqi@chenqi-laptop ~/MyPro/CFiles/IPC/msg_queue $ ipcs -q

------ Message Queues --------
key        msqid      owner      perms      used-bytes   messages    

chenqi@chenqi-laptop ~/MyPro/CFiles/IPC/msg_queue $ ipcs -s

------ Semaphore Arrays --------
key        semid      owner      perms      nsems     
0xcbc384f8 0          chenqi     600        1         

 

chenqi@chenqi-laptop ~/MyPro/CFiles/IPC/msg_queue $ ipcs -q

------ Message Queues --------
key        msqid      owner      perms      used-bytes   messages   
0x000004d2 32768      chenqi     666        0            0      

 

chenqi@chenqi-laptop ~/MyPro/CFiles/IPC/msg_queue $ ipcrm -q 32768
msgrcv failed with error 43
[1]+  Exit 1                  ./recv