Often, you may find that you need to operate on many files on a disk. Specifying one file at a time for one operation can be tedious. If these files have certain similarities in their file names, they can be referred to collectively using the wildcard facility provided by DOS. Suppose a disk contains the following files:
| ABC. EXE | ANNUAL.COB |
| ATTN.TXT | GO.EXE |
| APP.COB | ATTL.COB |
| ANN.TXT | ONE.COB |
| PEN.COB | ANNUAL.TXT |
You may need to work on only those files whose primary name is less than, or equal to, four characters and whose file name extension is .COB. Instead of selecting these files one by one, you can use the facility of wildcards, whereby you can specify a wildcard pattern with a command. DOS will refer to those files whose names match the specified wildcard pattern. Let us look at how the wildcards ? and * are used in commands.