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19.3.1 Syntax of Logical Pathname Namestrings

The syntax of a logical pathname namestring is as follows. (Note that unlike many notational descriptions in this document, this is a syntactic description of character sequences, not a structural description of objects.)

logical-pathname::=
[host host-marker]
[relative-directory-marker] {directory directory-marker}*
[name] [type-marker type [version-marker version]]
host::=
word
directory::=
word | wildcard-word | wild-inferiors-word
name::=
word | wildcard-word
type::=
word | wildcard-word
version::=
pos-int | newest-word | wildcard-version

host-marker—a colon.

relative-directory-marker—a semicolon.

directory-marker—a semicolon.

type-marker—a dot.

version-marker—a dot.

wild-inferiors-word—The two character sequence “**” (two asterisks).

newest-word—The six character sequence “newest” or the six character sequence “NEWEST”.

wildcard-version—an asterisk.

wildcard-word—one or more asterisks, uppercase letters, digits, and hyphens, including at least one asterisk, with no two asterisks adjacent.

word—one or more uppercase letters, digits, and hyphens.

pos-int—a positive integer.

19.3.1.1 Additional Information about Parsing Logical Pathname Namestrings
19.3.1.1.1 The Host part of a Logical Pathname Namestring

The host must have been defined as a logical pathname host; this can be done by using setf of logical-pathname-translations.

The logical pathname host name "SYS" is reserved for the implementation. The existence and meaning of SYS: logical pathnames is implementation-defined.

19.3.1.1.2 The Device part of a Logical Pathname Namestring

There is no syntax for a logical pathname device since the device component of a logical pathname is always :unspecific; see Section 19.3.2.1 (Unspecific Components of a Logical Pathname).

19.3.1.1.3 The Directory part of a Logical Pathname Namestring

If a relative-directory-marker precedes the directories, the directory component parsed is as relative; otherwise, the directory component is parsed as absolute.

If a wild-inferiors-marker is specified, it parses into :wild-inferiors.

19.3.1.1.4 The Type part of a Logical Pathname Namestring

The type of a logical pathname for a source file is "LISP". This should be translated into whatever type is appropriate in a physical pathname.

19.3.1.1.5 The Version part of a Logical Pathname Namestring

Some file systems do not have versions. Logical pathname translation to such a file system ignores the version. This implies that a program cannot rely on being able to store more than one version of a file named by a logical pathname.

If a wildcard-version is specified, it parses into :wild.

19.3.1.1.6 Wildcard Words in a Logical Pathname Namestring

Each asterisk in a wildcard-word matches a sequence of zero or more characters. The wildcard-word*” parses into :wild; other wildcard-words parse into strings.

19.3.1.1.7 Lowercase Letters in a Logical Pathname Namestring

When parsing words and wildcard-words, lowercase letters are translated to uppercase.

19.3.1.1.8 Other Syntax in a Logical Pathname Namestring

The consequences of using characters other than those specified here in a logical pathname namestring are unspecified.

The consequences of using any value not specified here as a logical pathname component are unspecified.