.\" Added msqid_ds and ipc_perm structure definitions
.\" 2005-08-02, mtk: Added IPC_INFO, MSG_INFO, MSG_STAT descriptions
.\"
-.TH MSGCTL 2 2012-05-31 "Linux" "Linux Programmer's Manual"
+.TH MSGCTL 2 2014-02-24 "Linux" "Linux Programmer's Manual"
.SH NAME
msgctl \- System V message control operations
.SH SYNOPSIS
.BR msgctl ()
performs the control operation specified by
.I cmd
-on the System V message queue with identifier
+on the System\ V message queue with identifier
.IR msqid .
.PP
The
.RI ( msg_perm.cuid )
of the message queue, or the caller must be privileged.
Appropriate privilege (Linux: the
-.B CAP_IPC_RESOURCE
+.B CAP_SYS_RESOURCE
capability) is required to raise the
.I msg_qbytes
value beyond the system parameter
The calling process must have appropriate privileges
or its effective user ID must be either that of the creator or owner
of the message queue.
+The third argument to
+.BR msgctl ()
+is ignored in this case.
.TP
.BR IPC_INFO " (Linux-specific)"
-Returns information about system-wide message queue limits and
+Return information about system-wide message queue limits and
parameters in the structure pointed to by
.IR buf .
This structure is of type
for details.
.TP
.BR MSG_INFO " (Linux-specific)"
-Returns a
+Return a
.I msginfo
structure containing the same information as for
.BR IPC_INFO ,
in all queues on the system.
.TP
.BR MSG_STAT " (Linux-specific)"
-Returns a
+Return a
.I msqid_ds
structure as for
.BR IPC_STAT .
(as found in
.IR msg_perm.uid )
of the message queue,
-and the process is not privileged (Linux: it does not have the
+and the caller is not privileged (Linux: does not have the
.B CAP_SYS_ADMIN
capability).
+.TP
+.B EPERM
+An attempt
+.RB ( IPC_SET )
+was made to increase
+.I msg_qbytes
+beyond the system parameter
+.BR MSGMNB ,
+but the caller is not privileged (Linux: does not have the
+.B CAP_SYS_RESOURCE
+capability).
.SH CONFORMING TO
SVr4, POSIX.1-2001.
.\" SVID does not document the EIDRM error condition.
.BR capabilities (7),
.BR mq_overview (7),
.BR svipc (7)
+.SH COLOPHON
+This page is part of release 3.68 of the Linux
+.I man-pages
+project.
+A description of the project,
+information about reporting bugs,
+and the latest version of this page,
+can be found at
+\%http://www.kernel.org/doc/man\-pages/.