NAME

ipcs – show information on IPC facilities  

SYNOPSIS

ipcs [options]  

DESCRIPTION

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.  

OPTIONS

-i, –id id
Show full details on just the one resource element identified by id. This option needs to be combined with one of the three resource options: -m, -q or -s.
-h, –help
Display help text and exit.
-V, –version
Display version information and exit.
 

Resource options

-m, –shmems
Write information about active shared memory segments.
-q, –queues
Write information about active message queues.
-s, –semaphores
Write information about active semaphore sets.
-a, –all
Write information about all three resources (default).
 

Output formats

Of these options only one takes effect: the last one specified.
-c, –creator
Show creator and owner.
-l, –limits
Show resource limits.
-p, –pid
Show PIDs of creator and last operator.
-t, –time
Write time information. The time of the last control operation that changed the access permissions for all facilities, the time of the last msgsnd() and msgrcv() operations on message queues, the time of the last shmat() and shmdt() operations on shared memory, and the time of the last semop() operation on semaphores.
-u, –summary
Show status summary.
 

Representation

These affect only the -l (–limits) option.
-b, –bytes
Print sizes in bytes.
–human
Print sizes in human-readable format.
 

Willie has over 15 years of experience in Linux system administration and DevOps. After managing infrastructure for startups and enterprises alike, he founded Command Linux to share the practical knowledge he wished he had when starting out. He oversees content strategy and contributes guides on server management, automation, and security.