How To Program Key Strokes Via Command Line

The KEYSTACK command is a useful tool for sending keystrokes to a program or command. It overcomes two weaknesses of input redirection: some programs ignore standard input and read the keyboard through Windows APIs, and input redirection doesn't end until the program or command terminates. With KEYSTACK, you can send a series of keystrokes to a program as if they were typed at the keyboard. Once the KEYSTACK buffer is empty, the program will receive further input from the keyboard.

To use KEYSTACK, you need to specify the window you want to send the keystrokes to. You can choose between the "Current Window" and the "Specified Window". If you select "Specified Window", you will need to enter the caption of the window or activate the window before running the KEYSTACK command.

KEYSTACK is often used for programs started from batch files. To make it work in a batch file, you need to start the program with the START command and then use the KEYSTACK command. If you don't use the START command, the batch file will wait for the application to complete before running the KEYSTACK command, and the keystrokes will not appear in the target program.

When using KEYSTACK, you can enter literal characters, key names, or ASCII codes. Characters entered within double quotes will be sent to the target program as is. For example, to insert the string "abc", you would use the command "keystack "abc"". If the keyname is a single letter, it will be inserted into the keystack buffer as if it were quoted without any spaces. For instance, the string "abc" can be entered as "a b c". If the keyname is a number, it is interpreted as a virtual key code (0-255).

You can also repeat keystrokes by following the keyname with a space, a left bracket, the repetition count, and a right bracket. For instance, to send the Enter key four times, you would use the command "keystack [Enter] [4]". It's important to note that the repeat count only works with individual key names and cannot be used with quoted strings.

KEYSTACK allows for delays between keystrokes, specified in clock ticks, which are approximately 1/18 of a second each. This can be useful for giving the program time to start up or respond to key presses.

Overall, KEYSTACK is a versatile tool for sending keystrokes to programs or commands, offering flexibility in terms of character input, repetition, and delays.

Using xdotool to send keystrokes to a GUI program

Injecting keystrokes into a GUI program can be done using the `xdotool command. This allows you to send keystrokes to a specific window, which can be selected by its ID or name.

To send keystrokes to a GUI program, you first need to find the window ID of the target window. This can be done using the `xdotool` command with the search option, followed by either the --class or --name option to specify the window by its class or name, respectively. For example:

Bash

Xdotool search --class Chrome

Or:

Bash

Xdotool search --name "YouTube"

If the `search` command returns multiple windows, you can use the windowactivate option to activate a specific window before injecting the keystrokes. The following command sends the "F5" keystroke to the first Chrome window:

Bash

Xdotool search --class Chrome windowactivate --sync %1 key F5 windowactivate $(xdotool getactivewindow)

Note that many applications reject synthetic events, so you may need to inject the keystroke using a different mechanism or focus the target window.

Alternatively, you can use a nested X server to input keystrokes without changing the focus or grabbing the keyboard. This can be done using the `Xephyr` command:

Bash

Xephyr -resizeable :13

Export DISPLAY=:13

Xterm

Xdotool type rhabarber

This starts the `Xephyr` nested X server and sets the `$DISPLAY` environment variable to `:13`, so any X application started after this will connect to `Xephyr`. The `xterm` command starts the target application, and `xdotool` is used to send the keystrokes.

Using PowerShell to press a key

PowerShell is a cross-platform automation tool and configuration framework that includes a command-line shell, an object-oriented scripting language, and tools for executing scripts and managing modules. It can be used to simulate keystrokes and send keystrokes to specific windows or applications.

To press a single key using PowerShell, you can use the SendKeys method from the WScript.Shell COM object. Here's an example code snippet:

Powershell

$wshell = New-Object -ComObject WScript.Shell

$wshell.SendKeys('q')

In this code, we first create an instance of the WScript.Shell object and store it in the $wshell variable. Then, we use the SendKeys method to simulate pressing the 'q' key. You can replace 'q' with any other key you want to press.

If you want to press and hold a key for a specific duration, you can use the Start-Sleep cmdlet to introduce a delay. For example:

Powershell

$wshell = New-Object -ComObject WScript.Shell

$wshell.SendKeys('q')

Start-Sleep -Seconds 1

In this code, after pressing the 'q' key, the script will pause for 1 second before continuing.

You can also use the System.Windows.Forms.SendKeys class to send keystrokes. This approach may provide more flexibility in certain scenarios. Here's an example:

Powershell

Add-Type -AssemblyName System.Windows.Forms

[System.Windows.Forms.SendKeys]::SendWait('q')

In this code, we first load the System.Windows.Forms assembly using the Add-Type cmdlet. Then, we use the SendWait method from the SendKeys class to send the 'q' keystroke.

If you need to send keystrokes to a specific application or window, you can use the AppActivate method to activate the desired window before sending the keystrokes. For example:

Powershell

$processName = Get-Process -Name Calculator

$wshell = New-Object -ComObject WScript.Shell

$wshell.AppActivate($processName.MainWindowTitle)

[System.Windows.Forms.SendKeys]::SendWait('q')

In this code, we first get the process name of the Calculator application and then use AppActivate to activate its window. Finally, we send the 'q' keystroke to that window.

Additionally, you can use tools like RoboTask or TCC (formerly known as 4NT) to easily send keystrokes to applications. These tools provide graphical interfaces and additional features for automating tasks and sending keystrokes.

Using WinSendKeys to send keystrokes

WinSendKeys is a Sendkeys R package for Windows that allows users to send keystrokes to a specified window. It provides two main functions: activateWindow and sendKeys. The activateWindow function brings the specified window into focus, while the sendKeys function sends keystrokes to the specified window.

To install WinSendKeys, you can use the package remotes in R by running the following command:

> remotes::install_github("miraisolutions/winsendkeys")

If you are behind a proxy, you can configure this by setting the https_proxy environment variable:

> Sys.setenv(https_proxy="http://:@:")

WinSendKeys offers a simple way to automate tasks that require sending specific keystrokes to a particular window. This can be useful for repetitive tasks or for accessing menu commands using shortcut keys. For example, sending "ALT + F" will open the File menu in most Windows applications.

It's important to note that WinSendKeys sends keystrokes to the currently active window by default. If you want to send keystrokes to a different window, you need to activate that window first. This can be done by specifying the window's caption or using other window activation techniques.

Additionally, WinSendKeys allows for delays between keystrokes, which can be crucial for giving the target application time to respond. These delays are specified in milliseconds and ensure that the keystrokes are interpreted correctly by the application.

Overall, WinSendKeys provides a straightforward way to send keystrokes to specific windows, enabling automation and streamlining various tasks on Windows systems.

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