The WILDMAT format was first developed by Rich Salz based on
    the format used in the UNIX "find" command to articulate
    file names. It was developed to provide a uniform mechanism
    for matching patterns in the same manner that the UNIX shell
    matches filenames. Patterns are implicitly anchored at the
    beginning and end of each string when testing for a match.
    There are five pattern matching operations other than a strict
    one-to-one match between the pattern and the source to be
    checked for a match. The first is an asterisk (*) to match
    any sequence of zero or more characters. The second is a
    question mark (?) to match any single character. The third
    specifies a specific set of characters. The set is specified as
    a list of characters, or as a range of characters where the
    beginning and end of the range are separated by a minus (or dash)
    character, or as any combination of lists and ranges. The dash can
    also be included in the set as a character it if is the beginning
    or end of the set. This set is enclosed in square brackets. The
    close square bracket (]) may be used in a set if it is the first
    character in the set. The fourth operation is the same as the
    logical not of the third operation and is specified the same
    way as the third with the addition of a caret character (^) at
    the beginning of the test string just inside the open square
    bracket. The final operation uses the backslash character to
    invalidate the special meaning of the a open square bracket ([),
    the asterisk, backslash or the question mark. Two backslashes in
    sequence will result in the evaluation of the backslash as a
    character with no special meaning.

NNTP-Ext 3.3.1 Examples

    a. [^]-] -- matches any single character other than a close square
                bracket or a minus sign/dash.

    b. *bdc  -- matches any string that ends with the string "bdc"
                including the string "bdc" (without quotes).

    c. [0-9a-zA-Z] -- matches any single printable alphanumeric ASCII
                character.

    d. a??d  --  matches any four character string which begins
                 with a and ends with d.