CLHS: Function PATHNAME

#

Function PATHNAME

Syntax:

pathname pathspec => pathname

Arguments and Values:

pathspec---a pathname designator.

pathname---a pathname.

Description:

Returns the pathname denoted by pathspec.

If the pathspec designator is a stream, the stream can be either open or closed; in both cases, the pathname returned corresponds to the filename used to open the file. pathname returns the same pathname for a file stream after it is closed as it did when it was open.

If the pathspec designator is a file stream created by opening a logical pathname, a logical pathname is returned.

Examples:

     ;; There is a great degree of variability permitted here.  The next
     ;; several examples are intended to illustrate just a few of the many
     ;; possibilities.  Whether the name is canonicalized to a particular
     ;; case (either upper or lower) depends on both the file system and the
     ;; implementation since two different implementations using the same
     ;; file system might differ on many issues.  How information is stored
     ;; internally (and possibly presented in #S notation) might vary,
     ;; possibly requiring `accessors' such as PATHNAME-NAME to perform case
     ;; conversion upon access.  The format of a namestring is dependent both
     ;; on the file system and the implementation since, for example, one
     ;; implementation might include the host name in a namestring, and
     ;; another might not.  #S notation would generally only be used in a
     ;; situation where no appropriate namestring could be constructed for use
     ;; with #P.
     (setq p1 (pathname "test"))
    =>  #P"CHOCOLATE:TEST" ; with case canonicalization (e.g., VMS)
    OR=>  #P"VANILLA:test"   ; without case canonicalization (e.g., Unix)
    OR=>  #P"test"
    OR=>  #S(PATHNAME :HOST "STRAWBERRY" :NAME "TEST")
    OR=>  #S(PATHNAME :HOST "BELGIAN-CHOCOLATE" :NAME "test")
     (setq p2 (pathname "test"))
    =>  #P"CHOCOLATE:TEST"
    OR=>  #P"VANILLA:test"
    OR=>  #P"test"
    OR=>  #S(PATHNAME :HOST "STRAWBERRY" :NAME "TEST")
    OR=>  #S(PATHNAME :HOST "BELGIAN-CHOCOLATE" :NAME "test")
     (pathnamep p1) =>  true
     (eq p1 (pathname p1)) =>  true
     (eq p1 p2)
    =>  true
    OR=>  false
     (with-open-file (stream "test" :direction :output)
       (pathname stream))
    =>  #P"ORANGE-CHOCOLATE:>Gus>test.lisp.newest"

Affected By: None.

Exceptional Situations: None.

See Also:

pathname, logical-pathname, Section 20.1 (File System Concepts), Section 19.1.2 (Pathnames as Filenames)

Notes: None.

The following X3J13 cleanup issues, not part of the specification, apply to this section:

- FILE-OPEN-ERROR:SIGNAL-FILE-ERROR
- PATHNAME-LOGICAL:ADD
- CLOSED-STREAM-OPERATIONS:ALLOW-INQUIRY
- PATHNAME-STREAM

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