siadat / ipc

Pure Go wrapper for System V message queue

System V message queue IPC functions

Wrapper functions for System V Message Queue IPC.

Example

package main

import (
	"log"
	"syscall"

	"github.com/siadat/ipc"
)

func main() {
	key, err := ipc.Ftok("/dev/null", 42)
	if err != nil {
		panic(err)
	}

	qid, err := ipc.Msgget(key, ipc.IPC_CREAT|ipc.IPC_EXCL|0600)
	if err == syscall.EEXIST {
		log.Fatalf("queue(key=0x%x) exists", key)
	}
	if err != nil {
		log.Fatal(err)
	}

	msg := &ipc.Msgbuf{Mtype: 12, Mtext: []byte("message")}
	err = ipc.Msgsnd(qid, msg, 0)
	if err != nil {
		log.Fatal(err)
	}
}

ipc's Issues

regarding key and qid

is key or message queue id (qid) <== this going to be different if i ran the program for a long time (e.g. forever)
coz i would like to init once instead of going to get the msqid all the time.

will it change during the runtime of the program? otherwise i just init as a variable and use everywhere for the duration of the daemon program

	key, err := ipc.Ftok(ftokpath, ftokid)
	if err != nil {
		log.Fatal(err)
	}

	var qid uint

	switch os.Args[1] {
	case "s", "r":
		qid, err = ipc.Msgget(key, ipc.IPC_CREAT|perm)

license?

Looks like a nice project! Can you please consider adding a license file using either MIT or Apache?

migrate to pure go

Hi
we are using ipc message queues widely in our c projects, I want to add new app written in go
is it possible to migrate project to pure go and don't use cgo?
we want to use it on aix(7.2) and we didn't manage to setup cgo(it's not possible to connect it to internet, but dependencies need internet connection)

thanks

func Msgrcv can't work well

line 36 : mtype uint64 has not been changed。 becasue line37 is binary.read，not func binary.write

Lost bytes when running on ARM7

Hello,
I try to use your lib on a raspberry pi (raspbian based ), I've just used your Msgrcv test as example, it works well on a x86 computer, but on an ARM7 Everytime I lost the 4th first bytes.

Generate key 705037316
Create ipc queue id 0
Message [24 45 68 0 251 33 9 64] send to ipc id 0
Message [24 45 68 0 0 0 0 0] receive to ipc id 0
2019/11/28 16:50:34 Input = [24 45 68 0 0 0 0 0], want [24 45 68 0 251 33 9 64]

It's probably an issue with cgo but to you have an idea for fixing that ?

Thank you

what's the message size limit and is it using /dev/shm in linux or...?

what's the message size limit and is it using /dev/shm in linux or...?
what if oom?

ipc.Msgctl can not use

I want to get stat, but no any function can use.

this code can't return any data.

ipc.Msgctl(qid, ipc.IPC_STAT)

please provide ipc benchmark report ?

thank u

Version

Hi,

could you please consider tagging/creating a release for this project (whatever the number)? It's stable enough for us to use in production and it would be easier in our go.mod to reference a version instead of a commit.

Thanks!

can u pls help explain the following?

sorry a bit dense but what does path, id and mtype mean?

        ftokpath := "."
        ftokid := uint('m')
        mtype := uint(42)