Some SMB requests allow wildcards to be given for the filename. The wildcard allows a number of files to be operated on as a unit without having to separately enumerate the files and individually operate on each one from the client.
If the client is using 8.3 names, each part of the name ( base (8) or extension (3) ) is treated separately. For long filenames the . in the name is significant even though there is no longer a restriction on the size of each of the components.
The ? character is a wild card for a single character. If a filename part commences with one or more "?"s then exactly that number of characters will be matched by the wildcards, e.g., "??x" equals "abx" but not "abcx" or "ax". When a filename part has trailing "?"s then it matches the specified number of characters or less, e.g., "x??" matches "xab", "xa" and "x", but not "xabc". If only "?"s are present in the filename part, then it is handled as for trailing "?"s
The * character matches an entire part of the name, as does an empty specification for that part. A part consisting of * means that the rest of the component should be filled with ? and the search should be performed with this wildcard character. For example, "*.abc" or ".abc" match any file with an extension of "abc". "*.*", "*" or "null" match all files in a directory.
If the negotiated dialect is "NT LM 0.12" or later, and the client requires MS-DOS wildcard matching semantics, UNICODE wildcards should be translated according to the following rules:
Translate the ? literal to >
Translate the . literal to " if it is followed by a ? or a *
Translate the * literal to < if it is followed by a .
The translation can be performed in-place.