June 2002
Beginner
759 pages
80h 42m
English
msgctl
msgctl id, cmd, arg
Calls the msgctl
system call, which is used to perform different control operations
on IPC message queues. (See the msgctl documentation on your system for
details.) If cmd is &IPC_STAT, then
argmust be a variable that will hold
the returned msqid_ds
structure. The return values work like those of fnctl: the undefined value for error,
0 but true for zero, or the actual return
value otherwise. On error, it puts the error code into $!. Before calling, you should
say:
require "ipc.ph"; require "msg.ph";
This function is available only on machines supporting System V IPC.