In the daily work of software development, we often encounter tricky “minor issues” that seem simple but can consume us hours of valuable time. One such “disaster zone” is deleting specific files – particularly those generated unexpectedly by toolchains.

I encountered a “level-boss” problem: during local development, a file named nul inexplicably appeared in my project. I tried Windows Explorer, the CMD command line, but the system displayed “File not found” or “Cannot delete.” This file was like a ghost, stubbornly residing in my project directory.

Phase One: Routine Attempts and the Ineffective Solution of “Standard” Approaches

When I encounter this problem, my first instinct is to create a nul file. Why is nul special?

Developers familiar with Windows history may know that nul is a “trap.” In Windows (and earlier DOS) systems, NUL, CON, PRN, AUX, etc., are reserved device names. NUL represents the “null device” (similar to Unix/Linux’s /dev/null).

When the Windows file system API sees you trying to operate a “file” named nul, it treats it as an operation on this “null device,” rather than a filename with the same name. Therefore, all standard file operations (such as deleting or renaming) fail. How are nul files created?

This is usually the fault of cross-platform development tools (like Git, Node.js scripts, Python scripts, etc.). These tools may be based on POSIX (Unix-like) standards, in which case nul is simply a regular filename to them. When they run on Windows, they sometimes bypass standard APIs and create this “Windows-unfriendly” file. “Standard” Solutions Recommended Online

I quickly searched the web and found that I wasn’t the first person to encounter this problem. The community offered several “advanced” solutions that were widely accepted:

1. Use the \\.\ syntax: In CMD, use the special “long path” syntax to bypass Windows name checking.

   del \\.\C:\your\project\path\nul
   

2. Use Git Bash: Git Bash provides a lightweight Unix environment, which doesn’t treat nul as a special device.

   rm nul
   

3. Use WSL (Windows Subsystem for Linux): Enter WSL, mount the Windows disk, and use the Linux rm command to delete.

   rm /mnt/c/your/project/path/nul
   

However, none of these methods worked for me! Whether it was WSL or Git Bash, when I tried rm nul, the system reported a “No such file or directory” error. This led me to ponder the problem seemed more complex than I initially thought.

Stage Two: A Flash of Insight – Is it “Multiple Problem Overlapping”?

If the nul file actually existed, why were even Unix tools saying “cannot find” it?

I began to suspect that the problem wasn’t just with the nul file itself, but also with its “habitat” – the directory where it was located?

I immediately opened Git Bash (this was key, because Windows Explorer might not display anomalies), navigated to the directory containing the nul file, and then executed ls -la (list all files, including hidden ones, and show detailed information).

That’s when I finally discovered the “blind spot”: the directory where the nul file was stored actually contained an illegal character within its name!

Stage Two: A Flash of Insight – Is it “Multiple Problem Overlap”?

In my case, this directory name might be one ending with a space or a period (.) or containing special characters (like ?, *, :) that development tools “carry along” when syncing across platforms—these are all equally problematic.

For example, a directory displayed in Git Bash as "my-app " (note the trailing space) or "my-app.".

That’s where the problem lies!

• Problem A: I have an “illegal” file named nul.
• Problem B: I have an “illegal” directory named "my-app ".

When I try rm /path/to/"my-app "/nul, both the Windows system and Unix tools are “confused.” The Windows API cannot correctly parse this path containing illegal characters; while Git Bash or WSL might “see” this illegal directory, it may fail to access its internal nul file due to complex path parsing issues.

Phase Three: Cutting Off the Root – Targeting the Path, Eliminating Everything in One Go

Now that we’ve confirmed it was a problem with both “file path” and “filename,” the solution became clear: don’t try to delete that nul file; instead, directly delete that “illegitimate” parent directory!

My final resolution steps were as follows:

1. Open Git Bash: This is the only tool capable of correctly “seeing” and handling these illegal names.
2. Navigate to the parent directory of the “problem directory”:
3. Verify the true name of the “problem directory”:
4. Execute the “Ultimate Delete”: Using the rm command with the -r (recursive) and -f (force) options, combined with quotes, to delete the entire directory.

After executing the command, the troublesome directory containing the nul file, which itself had an invalid name, was finally completely removed from my filesystem.