UNIX isn’t alone in being persnickety about creating and finding filenames and pathnames. Keep the following tips in mind as you create and search through UNIX files:

  • Capital and small letters are different in filenames.

  • Filenames can contain letters, numbers, periods, and underscores (_). Stay away from other punctuation. Slashes are special (see below).

  • Filenames shouldn’t contain spaces.

  • The ? wildcard stands for a single character in a filename. The * wildcard stands for a bunch of characters in a filename. An * by itself stands for all files in the working directory.

  • A pathname is the path in which you (or UNIX) can find a file or directory. The root (main) directory of the disk is called /.

  • A pathname consists of directory names separated by slashes (/). If a pathname starts with a slash (/), it begins at the root directory. If a pathname doesn’t start with a slash, it begins at the working directory.