In some situations, it's important to ensure that a Batch script runs only once at a time, in order to preserve the integrity of resources that cannot be shared or accessed concurrently. While implementing a mutex is straightforward in PowerShell or other .NET languages, the default Windows Shell does not provide an equally simple mechanism to prevent parallel execution of Batch scripts. In this post, I explore several workaround methods for identifying and managing a single running instance of a Batch script. 1. Using a Lock File One of the simplest techniques for achieving mutual exclusion in Batch scripts is the use of a lock file. When the script starts, it creates a specific file to signal that an instance is already running. Upon completion, the script deletes the lock file. If another instance of the script is launched while the lock file exists, it detects the file's presence and exits immediately, preventing parallel execution. Here's...

Obtaining the PID of the current Command Prompt process is not straightforward. Unlike PowerShell, Batch scripting does not provide an automatic variable for this information. In this post, I detail the subtle complexities involved in retrieving the current PID due to the limitations of Batch scripting. 1. Parent-Child Relationship Between Processes Although, I will only describe a method that uses PowerShell to retrieve the PID, but it's important to understand that this capability is not unique to PowerShell. In fact, it is inherent to any console application that can easily access its own PID while running. This is particularly relevant for console applications built with .NET Framework languages such as C#, VB.NET, or JScript.NET, which — like PowerShell — are typically installed by default on Windows systems. By launching one of these applications from the Command Prompt, you create a parent-child relationship between the Command Prompt (the p...

To assign drive letters, I initially relied on the Disk Management console ( diskmgmt.msc ). While the task seemed simple, repeating it after each fresh Windows installation became time-consuming. To streamline the process, I developed a Batch script that automates drive letter assignments using embedded DiskPart commands. In this post, I focus specifically on the DiskPart-related aspects. You can view the complete script by visiting the project on GitHub . 1. Assigning an Unavailable Letter to a Partition This is the problem my Batch script was designed to solve. When using the Disk Management interface to change a drive letter, the dropdown menu only displays letters that are currently available. Similarly, DiskPart throws an error if a user tries to assign a letter that is already in use by another partition — other than the one being modified. The solution can be summarized as follows: if the desired drive letter is already in use, first remo...