DOS‐tips

PC users who deal with large numbers of files using the DOS COPY command should be aware of an obscure bug in DOS version 2.1. If you use the “*.*” wildcard specification (meaning “all files in the current directory”) to copy more than 256 files, every 256th file will not actually be copied. What's worse, if you delete the original files after the copying is complete, that 256th file is gone forever! And who is going to notice one missing file among more than 250? That is, until the program that uses that file misbehaves unexpectedly, or until you actually need to update last month's circulation statistics report.