coreybutler/nvm-windows · error

failed to copy data: %w

Error message

failed to copy data: %w

What it means

In copyFile(), io.Copy(destFile, srcFile) streams the file contents. This error means the byte transfer failed partway — destination writes failed (disk full, quota exceeded) or the source read failed (I/O error, file truncated underneath, handle invalidated). The destination file may be left partially written.

Source

Thrown at src/utility/rename.go:70

	}
	defer srcFile.Close()

	// Ensure destination directory exists
	destDir := filepath.Dir(new)
	err = os.MkdirAll(destDir, os.ModePerm)
	if err != nil {
		return fmt.Errorf("failed to create destination directory: %w", err)
	}

	destFile, err := os.Create(new)
	if err != nil {
		return fmt.Errorf("failed to create destination file: %w", err)
	}
	defer destFile.Close()

	_, err = io.Copy(destFile, srcFile)
	if err != nil {
		return fmt.Errorf("failed to copy data: %w", err)
	}

	// Copy file permissions
	info, err := srcFile.Stat()
	if err != nil {
		return fmt.Errorf("failed to get source file info: %w", err)
	}
	err = os.Chmod(new, info.Mode())
	if err != nil {
		return fmt.Errorf("failed to set permissions on destination file: %w", err)
	}

	return nil
}

// copyDir recursively copies a directory from old path to new path.
func copyDir(old, new string) error {
	entries, err := os.ReadDir(old)

View on GitHub (pinned to 5b18223ca1)

Solutions

1. Check the wrapped error for 'There is not enough space on the disk' and free space, then retry.
2. If the source is on removable/network media, verify it is still mounted and readable, then retry.
3. Delete the partially-written destination file before retrying so sizes can be compared afterward.
4. Run chkdsk on the suspect volume if repeated I/O errors occur.

// Compare free space with source size before copying
func enoughSpace(dst string, need int64) bool {
    var st syscall.Statfs_t // platform-specific; use golang.org/x/sys/windows GetDiskFreeSpaceEx on Windows
    _ = st
    return true // replace with real check
}

err := copyAcrossDrives(old, new)
for attempts := 0; err != nil && strings.Contains(err.Error(), "failed to copy data") && attempts < 3; attempts++ {
    os.Remove(new) // drop partial file
    time.Sleep(500 * time.Millisecond)
    err = copyAcrossDrives(old, new)
}

When it happens

Trigger: copyFile where the destination disk fills mid-copy, the source file is on a failing/removable drive that disappears, or an antivirus/filter driver aborts the read/write.

Common situations: Moving a large node version (node_modules with big binaries) to a nearly-full drive; USB/network drive dropouts; source on a drive with bad sectors; WebDAV/network filesystem timeouts.

Related errors

• failed to create destination file: %w
• failed to copy directory: %w
• failed to copy file: %w
• failed to open source file: %w
• failed to create destination directory: %w

AI-assisted analysis of coreybutler/nvm-windows@5b18223ca1 (2026-08-15). Data as JSON: /api/errors/8d0bb539d90388d7. Report an issue: GitHub.