File Types

• Regular files
• Directories
• Device Files
  • Character Devices
  • Block Devices
• Some systems distinguish between regular file types; ASCII text files, binary files
• A common implementation technique (as organizational help with consistent usage) is to include the type as an extension to the file name (see Fig. 6.1)
• Files are structured internally to meet the expectations of the program(s) that manipulate them.
• All systems recognize their own executable file format; May use a magic number (see Fig. 6.3)

Figure 6.3: (a) An executable file (b) An archive.