DIR$SYSTEM FunctionWindows

A system function used to obtain the first/next file corresponding to a specified filespec.

Syntax: DIR$[(file-spec, attribute)]
FileName$ = DIR$("*.*", 0) '-- Get first file
FileName$ = DIR$ '-- Get next file

Details:
File-spec specifies a filename or path (which can include wildcards characters). 
Calling DIR$ with no parameters return additional filename matches. If no matches exist (or all matches have been exhausted), DIR$ returns an empty string. DIR$ returns all regular files as well as any special files specified in the attribute parameter.
Here are some valid file attributes, you can combine
them by using OR (ie. faReadOnly OR faDirectory)

&H1 = faReadOnly       &H8 = faVolumeID
&H2 = faHidden        &H10 = faDirectory
&H4 = faSysFile       &H20 = faArchive
                      &H3F = faAnyFile
To obtain additional information on the currently matched file, use the FileRec properties.
FileRec.FileName    - Returns Windows long file name
FileRec.ShortName   - Returns the short file name
FileRec.Date        - Returns the file date as a string
FileRec.Time        - Returns the file time as a string
FileRec.Size        - Returns the file size
FileRec.FileTime    - Returns the file time as an integer
You can use FileRec.FileTime to compare file times. So a newer file will have a FileTime greater than an older file.