yes, you would have to allocate space for up to 100 file paths, but the article says > it’s more efficient because it reduces the amount of calls into the file

yes, you would have to allocate space for up to 100 file paths, but the article says > it’s more efficient because it reduces the amount of calls into the file system, which is where the bottleneck is Upon reading it a few times I think the article is alluding to a crappy two-pass solution where you don't store a filename but instead an index into a directory, which is flawed anyway due to being racy.