In what ways can the absence of a forward slash in the filesize function call impact the functionality of the download script?

The absence of a forward slash in the filesize function call can cause the script to not accurately retrieve the size of the file, leading to potential errors in the download process. To solve this issue, you need to include the correct file path with a forward slash in the filesize function call to ensure the accurate retrieval of the file size.

$file = "path/to/file.txt";
$filesize = filesize($file);