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What is the ISO 9660 Level 1 standard?

Fri, 09/07/2007 - 1:31pm — Digital Commons

ISO 9660-1 is the standard format for MS-DOS CD-ROMs, and is readable on Mac, Windows, and UNIX machines. However, it requires the following constraints on file names:

  • Filenames must ONLY consist of uppercase letters, numbers 0-9, and the underline dash (underscore) "_". If you have filenames with lowercase letters, they will automatically be converted to uppercase.
  • Filenames consist of EXACTLY one period ("."), a maximum of 8 characters before the period and maximum of 3 characters after the period. Directory names cannot have the 3-character extension.
  • Subdirectories are only allowed to nest up to eight levels deep.
  • The ISO 9660 standard automatically appends a semicolon (";") and a version number to every filename. These numbers are not visible to the end user, but we can change them if it is necessary for your application.

    • For more information about the ISO 9660 standard and about CD recording in general, consult The CD Information Center.