5.4 Name Mangling and Case

Back in the days of DOS and Windows 3.1, every filename was limited to eight upper-case characters, followed by a dot, and three more uppercase characters. This was known as the 8.3 format, and was a huge nuisance. Windows 95/98, Windows NT, and Unix have since relaxed this problem by allowing many more case-sensitive characters to make up a filename. Table 5.6 shows the current naming state of several popular operating systems.

Table 5.6: Operating System Filename Limitations

Operating System	File Naming Rules
DOS 6.22 or below	Eight characters followed by a dot followed by a three-letter extension (8.3 format); case insensitive
Windows 3.1 for Workgroups	Eight characters followed by a dot followed by a three-letter extension (8.3 format); case insensitive
Windows 95/98	127 characters; case sensitive
Windows NT	127 characters; case sensitive
Unix	255 characters; case sensitive

Samba still has to remain backwards compatible with network clients who store files only in the 8.3 format, such as Windows for Workgroups. If a user creates a file on a share called antidisestablishmentarianism.txt, a Windows for Workgroups client couldn't tell it apart from another file in the same directory called antidisease.txt. Like Windows 95/98 and Windows NT, Samba has to employ a special methodology of translating a long filename to an 8.3 filename in such a way that similar filenames will not cause collisions. This is called name mangling, and Samba deals with this in a manner that is similar, but not identical to, Windows 95 and its successors.

Using Samba
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