The FILE_READLINK function returns the path pointed to by UNIX symbolic links.
Result = FILE_READLINK(Path [, /ALLOW_NONEXISTENT] [, /ALLOW_NONSYMLINK] [, /NOEXPAND_PATH] )
Returns the path associated with a symbolic link.
A scalar string or string array containing the names of the symbolic links to be translated.
Set this keyword to return an empty string rather than throwing an error if Path contains a non-existent file.
Set this keyword to return an empty string rather than throwing an error if Path contains a path to a file that is not a symbolic link.
Set this keyword to cause FILE_READLINK to use Path exactly as specified, without expanding any wildcard characters or environment variable names included in the path. See FILE_SEARCH for details on path expansion.
Under Mac OS X, the /etc directory is actually a symbolic link. The following statement reads it and returns the location to which the link points:
path = FILE_READLINK('/etc')
It is possible to have chains of symbolic links, each pointing to another. The following function uses FILE_READLINK to iteratively translate such links until it finds the actual file:
FUNCTION RESOLVE_SYMLINK, path
savepath = path ; Remember last successful translation
WHILE (path NE '') DO BEGIN
path = FILE_READLINK(path, /ALLOW_NONEXISTENT, $ /ALLOW_NONSYMLINK)
IF (path NE '') THEN BEGIN
; If returned path is not absolute, use it to replace the
; last path segment of the previous path.
IF (STRMID(path, 0, 1) NE '/') THEN BEGIN
last = STRPOS(savepath, '/', /REVERSE_SEARCH)
IF (last NE -1) THEN path = STRMID(savepath, 0, last) $
+ '/' + path
ENDIF
savepath = path
ENDIF
ENDWHILE
; FILE_EXPAND_PATH removes redundant things like /./ from
; the result.
RETURN, FILE_EXPAND_PATH(savepath)
END
|
5.6 |
Introduced |