Calls the System V IPC function msgctl(2). You'll probably have to say
use IPC::SysV;
first to get the correct constant definitions. If CMD is IPC_STAT
, then ARG must be a variable that will hold the returned msqid_ds
structure. Returns like ioctl
: the undefined value for error, "0 but true"
for zero, or the actual return value otherwise. See also "SysV IPC" in perlipc, IPC::SysV
, and IPC::Semaphore
documentation.