September 2009
Beginner
942 pages
85h 34m
English
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Name
wall
Synopsis
wall [file] wall [-n] [message]
Write to all users. Depending on your Linux distribution, wall uses one of the two syntaxes shown. In both versions, the default is for wall to read a message from standard input and send the message to all users currently logged in, preceded by “Broadcast Message from . . . .” With the first syntax, which comes with Debian-based systems, for example, if file is specified, wall reads input from that file rather than from standard input, and only the super-user can write to a terminal if the user has disallowed messages. With the second syntax, distributed with Red Hat-based systems, for example, the text of the message can be included on the command line, and the message is limited to 20 lines. In this form, if -n is specified, the default banner message is replaced with “Remote broadcast message.” -n can only be specified by the super-user, and only if wall was installed set-group-id.
Example
Send the message contained in the file message.txt to all users:
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O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.Julian F.
I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.Addison B.
I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.Amir M.
I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.