Equivalent of /dev/mqueue to enumerate SysV message queues

Question

Linux supports two kinds of message queues: POSIX (i.e., those created by mq_open), and System V (i.e., those created by msgget). For POSIX message queues, mq_overview(7) documents that you can enumerate them via the mqueue virtual filesystem, usually mounted at /dev/mqueue. However, System V message queues don't show up there. How can I enumerate them?

Answer 1

The proc virtual filesystem holds this information: /proc/sysvipc/msg is a file containing a list of all System V message queues. The ipcs program uses this file and shows you the same information, but in a more human-readable format.