Batch file definition
A batch file is a type of script file in Windows that contains a sequence of commands for a computer's command line interface. It's used to automate repetitive tasks on a computer. Each command in a batch file is executed by the command line interpreter (like the Command Prompt in Windows) in the order they appear in the file. Batch files usually have a .bat or .cmd extension. They're simple to create with a basic text editor like Notepad.
See also: command-line interface
How a batch file works
Each line in the batch file corresponds to a command line. When you run the file, the command-line interpreter (such as Command Prompt in Windows) reads it and starts executing its commands. It processes each line up to the end-of-line character and then executes it before moving on to the next one.
Built-in commands are embedded into the command-line interpreter itself, like 'copy,' 'del,' or 'dir' in Windows. External commands are separate executable files that the batch file can call, like running a Python script or launching an app.
Advanced batch files can also handle more complex commands like repeating actions (loops), making choices (if statements), and handling unexpected errors.
Batch files can store information and take input from the user or another program, making them more flexible. They can also include error-handling mechanisms to manage unexpected situations in command execution.
A real-life example of a batch file use
Imagine you have a folder where you keep important work documents on your computer. You want to back up these documents to a separate drive daily. Doing this manually every day can be tedious and easy to forget. This is where a batch file comes in handy.
- It identifies the folder where your important documents are stored.
- It then copies all the documents from this folder to a backup folder on a different drive or location.
- You can set the batch file to run at a specific time each day using Windows Task Scheduler. For example, it could run every night at 10 pm.
- The batch file might also include a command to create a log file, noting the date and time of each backup. That way, you can confirm that your files have been backed up as expected.