local GZipOS = { [0] = "FAT filesystem (MS-DOS, OS/2, NT/Win32)",
                 [1] = "Amiga",
                 [2] = "VMS (or OpenVMS)",
                 [3] = "Unix",
                 [4] = "VM/CMS",
                 [5] = "Atari TOS",
                 [6] = "HPFS filesystem (OS/2, NT)",
                 [7] = "Macintosh",
                 [8] = "Z-System",
                 [9] = "CP/M",
                 [10] = "TOPS-20",
                 [11] = "NTFS filesystem (NT)",
                 [12] = "QDOS",
                 [13] = "Acorn RISCOS",
                 [255] = "Unknown" } 

return GZipOS