内容简介：ipcs是Linux下显示进程间通信设施状态的工具。可以显示消息队列、共享内存和信号量的信息。对于程序员非常有用，普通的系统管理员一般用不到此指令。
ipcs是 Linux 下显示进程间通信设施状态的工具。可以显示消息队列、共享内存和信号量的信息。对于 程序员 非常有用，普通的系统管理员一般用不到此指令。
ipcs shows information on the inter-process communication facilities for which the calling process has read access.By default it shows information about all three resources: shared memory segments, message queues, and semaphore arrays.
Without options, information shall be written in short format for message queues, shared memory segments, and semaphore sets that are currently active in the system. Otherwise, the information that is displayed is controlled by the options specified.-q : Write information about active message queues. -m : Write information about active shared memory segments. -s : Write information about active semaphore sets. -a, --all all (default)
------ Message Queues -------- key msqid owner perms used-bytes messages root@52coder:~# ipcs -m ------ Shared Memory Segments -------- key shmid owner perms bytes nattch status root@52coder:~# ipcs -s ------ Semaphore Arrays -------- key semid owner perms nsems root@52coder:~#
-c : Write creator’s user name and group name;.
-p : Write process number information. (Process ID of the last process to send a message and process ID of the last process to receive a message on message queues, process ID of the creating process, and process ID of the last process to attach or detach on shared memory segments.)
-t : Write time information. (Time of the last control operation that changed the access permissions for all facilities, time of the last msgsnd() and msgrcv() operations on message queues, time of the last shmat() and shmdt() operations on shared memory, and time of the last semop() operation on semaphores.)root@52coder:~# ipcs -c
------ Message Queues Creators/Owners --------
msqid perms cuid cgid uid gid
------ Shared Memory Segment Creators/Owners --------
shmid perms cuid cgid uid gid
------ Semaphore Arrays Creators/Owners --------
semid perms cuid cgid uid gid
root@52coder:~#
root@52coder:~#
root@52coder:~#
root@52coder:~# ipcs -p
------ Message Queues PIDs --------
msqid owner lspid lrpid
------ Shared Memory Creator/Last-op PIDs --------
shmid owner cpid lpid
root@52coder:~# ipcs -t
------ Message Queues Send/Recv/Change Times --------
msqid owner send recv change
------ Shared Memory Attach/Detach/Change Times --------
shmid owner attached detached changed
------ Semaphore Operation/Change Times --------
semid owner last-op last-changed
root@52coder:~#
root@52coder:~# ipcs --help
Usage:
ipcs [resource-option...] [output-option]
ipcs -m|-q|-s -i <id>
Show information on IPC facilities.
Options:
-i, --id <id> print details on resource identified by <id>
-h, --help display this help
-V, --version display version
Resource options:
-m, --shmems shared memory segments
-q, --queues message queues
-s, --semaphores semaphores
-a, --all all (default)
Output options:
-t, --time show attach, detach and change times
-p, --pid show PIDs of creator and last operator
-c, --creator show creator and owner
-l, --limits show resource limits
-u, --summary show status summary
--human show sizes in human-readable format
-b, --bytes show sizes in bytes
For more details see ipcs(1).
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