So I just randomly came across this utility built into Windows 7 that simply sends or waits for a signal (message). This could be useful for batch scripts that need to wait for something to happen on a local (or remote) machine.
Here is the help output from the command:
C:UsersAdministrator>waitfor /? WaitFor has two ways of working:Syntax 1: to send a signal WAITFOR [/S system [/U user [/P [password]]]] /SI signal Syntax 2: to wait for a signal WAITFOR [/T timeout] signal Description: This tool sends, or waits for, a signal on a system. When /S is not specified, the signal will be broadcasted to all the systems in a domain. If /S is specified, then the signal will be sent only to the specified system. Parameter List: /S system Specifies remote system to send signal to. /U [domain]user Specifies the user context under which the command should execute./P [password] Specifies the password for the given user context. /SI Sends the signal across the net to waiting machines /T timeout Number of seconds to wait for signal. Valid range is 1 - 99999. Default is to wait forever for signal. signal The name of the signal to wait for or to send. /? Displays this help message. NOTE: A system can wait for multiple unique signal names. The signal name cannot exceed 225 characters and cannot contain characters other than a-z, A-Z, 0-9 and ASCII characters in the range 128-255. Examples: WAITFOR /? WAITFOR SetupReady WAITFOR CopyDone /T 100 WAITFOR /SI SetupReady WAITFOR /S system /U user /P password /SI CopyDone
Let’s look at an example of how to use it. All we have to do is set up a listener, and then use another command prompt to send the signal to it. For the sake of example, we’ll use the message “blah“.
1. Set up the listener
Listening for a signal
2. Send the signal (from a different command prompt)
Send the signal
3. Observe the listener result
See listener results
And that’s all there is to it! A simple, but handy utility if you’re writing batch scripts! It even sends a signal to a remote system, using the /S switch! You could also use this utility with the Microsoft Deployment Toolkit (MDT) 2010, to help control the flow of your task sequence.
