Module nix::mqueue

Available on crate feature mqueue only.

Expand description

Posix Message Queue functions

Example

use nix::sys::stat::Mode;

const MSG_SIZE: mq_attr_member_t = 32;
let mq_name= CString::new("/a_nix_test_queue").unwrap();

let oflag0 = MQ_OFlag::O_CREAT | MQ_OFlag::O_WRONLY;
let mode = Mode::S_IWUSR | Mode::S_IRUSR | Mode::S_IRGRP | Mode::S_IROTH;
let mqd0 = mq_open(&mq_name, oflag0, mode, None).unwrap();
let msg_to_send = b"msg_1";
mq_send(&mqd0, msg_to_send, 1).unwrap();

let oflag1 = MQ_OFlag::O_CREAT | MQ_OFlag::O_RDONLY;
let mqd1 = mq_open(&mq_name, oflag1, mode, None).unwrap();
let mut buf = [0u8; 32];
let mut prio = 0u32;
let len = mq_receive(&mqd1, &mut buf, &mut prio).unwrap();
assert_eq!(prio, 1);
assert_eq!(msg_to_send, &buf[0..len]);

mq_close(mqd1).unwrap();
mq_close(mqd0).unwrap();

Further reading and details on the C API

Structs

Identifies an open POSIX Message Queue

Functions

Close a message queue

Get message queue attributes

Open a message queue

Receive a message from a message queue

mq_remove_nonblock

Convenience function. Removes O_NONBLOCK attribute for a given message queue descriptor Returns the old attributes

Send a message to a message queue

mq_set_nonblock

Convenience function. Sets the O_NONBLOCK attribute for a given message queue descriptor Returns the old attributes

Set the attributes of the message queue. Only O_NONBLOCK can be set, everything else will be ignored Returns the old attributes It is recommend to use the mq_set_nonblock() and mq_remove_nonblock() convenience functions as they are easier to use

Remove a message queue

Type Definitions

mq_attr_member_t