In the CLISP programming environment, file and directory handling are treated distinctly. The EXT:PROBE-PATHNAME function assesses if a given path points to an existing directory or regular file, returning specific values if found, and NIL otherwise.
Function EXT:PROBE-PATHNAME figures out whether teh argument refers to an existing directory or an existing regular file, and returns 4 values if the filesystem object exists.
POSIX:FILE-SIZE
FILE-WRITE-DATE
EXT:ABSOLUTE-PATHNAME
TRUENAME
Documentation
See CLISP implementation notes chapter 20
Directory functions
EXT:RENAME-DIRECTORY
EXT:DELETE-DIRECTORY
EXT:MAKE-DIRECTORY
EXT:DEFAULT-DIRECTORY
EXT:CD
EXT:DIR
DIRECTORY
EXT:PROBE-DIRECTORY
File functions
RENAME-FILE
DELETE-FILE
FILE-AUTHOR
FILE-AUTHOR always returns NIL
PROBE-FILE
Directory is not a file
You can use DIRECTORY or EXT:PROBE-PATHNAME to figure out whether a given namestring refers to a file or a directory.
CLISP provides separate directory functions, such as EXT:DELETE-DIRECTORY, EXT:RENAME-DIRECTORY et al.
CLISP has traditionally taken the view that a directory is a separate object and not a special kind of file, so whenever the standard says that a function operates on files without specifically mentioning that it also works on directories, CLISP SIGNALS an ERROR when passed a directory.
