 Hello and welcome. This video is part of a series for short. Check out the full playlist in the description of this video So they were gonna be looking at the wall command, which is a very useful command For if you have a multi-user system, you have a lot of people working in the shell You basically allows you to broadcast a message to every user on the system So wherever there are you know if they're in the shell all the shells will get this message It's also a great way to notify yourself You know you can write a script that monitors something which we'll get to in the next video and send yourself a message So you have something running in one shell that's on another screen another You know desktop or even running in the background and when it's done or a file gets changed or something you get the message Whatever shell you're in and if you're working the shell up, that's very useful so it's Gonna be installed on your system by default on pretty much every system I've ever been on It's just a wall command and I can take wall. You know hello world And there it says you know as a broadcast message from it tells you who is from you know what? Shell it was sent from and when it was sent and then the message So let me go ahead and I'm just gonna split my screen here. I'm gonna open up a bunch of Windows a little shell windows here So these are all different could be on a different monitor You could be ssh'd in and be working on one of these and I could be here and I can be like Oh, hey, I just want everyone a message wall lunchtime Pizza in break room and There everybody got that message. So if I'm in this shell here, you know, he says oh, you know Metal X 1000, you know, he said that you know, it's lunchtime. It's time to go have some lunch So you can see it went to all these different shells and so this is another example I'm gonna hear I can say the same thing, but obviously I can put the output of a command in there I'm trying to think of a good example. I'm just going to say Free so this is just an example. So I'll do that and output the that commands everyone's window, you know You wouldn't pipe that particular command to everyone's window But if you wanted to if you have a program running, you can have it, you know, send you stuff like that So let me go ahead and I'm just gonna show you you can say sleep I'm gonna give you a better example of this In the next tutorial where we're gonna go over monitoring files and directories for modification and changes And so that way if you're monitoring a file or a folder either waiting for something to happen to them Or you just expect maybe someone's modifying a file. They shouldn't you can get a notification right away Using this I'm gonna say sleep Five seconds and here I'll just do I Will do a command. I'll just say a buddy So that's running I'll be in this shell here clear the screen and Boop after five seconds. I got that message. So very useful. It doesn't it might mess up You know, it doesn't mess up the programs you're running But obviously it's kind of annoying if someone's working like if I was in Vim and I was you know typing something out Like this, let me real quick go back up here wait five seconds. Oops and again. I'm working here You know, you know that message kind of got in my way, but it just kind of clears out It doesn't actually interfere with what you're running other than it's kind of it might cover up what you're looking at So use it sparingly if you're on a multi-user system don't bug people But again, I mainly would use this to notify myself When a process done or if a file is modified or something where I just want to know no matter what shell I'm in When something happens, it's mainly sending messages to myself, but it's it's originally designed to Broadcast stuff to all the users on a system. So I hope you did find this useful it I've probably did a tutorial on this ten years ago. It's a very useful command And we're gonna go again into more detail give you a more practical use for it in the next video So be sure to stick around for that as we monitor files and folders for modifications and get notified When something happens Be sure to check out my website films by Chris calm That's Chris the caters link in the description of the video there You can search through all my videos you can search through all my notes and scripts under the I think a section is called scripts You go there and I have a little interface where you can search through them That's not the fastest interface. I do need to improve on that Leave me do a video about it probably talking about how horribly I designed it because I just kind of threw it together but it works well and Well enough good enough for now But there you can also go to my support section where you can support me through PayPal and patreon.com forward slash Milux 1,000 I appreciate support like that but also like share subscribe comment all that fun stuff I love that you watch my videos. I hope you share it with others look forward to seeing you seeing you Look forward to having you watch my videos again soon. I have another one in a couple days Thank you for watching and as always I hope that you have a great day