PLS Playlists
A PLS playlist uses numbered text fields to list media locations, titles, and optional durations.
A radio station's small PLS download can contain only an address and descriptive text. A playlist reader opens that address to obtain the ongoing audio; the downloaded text is not the recording.
The syntax associates fields through a shared entry number:
[playlist]
File1=Music/Opening.mp3
Title1=Opening song
Length1=180
File2=Music/Second.mp3
Title2=Second song
Length2=240
NumberOfEntries=2
Version=2
File1, Title1, and Length1 describe one entry. The second group describes another. Length values conventionally use seconds; −1 commonly represents an unknown duration, such as a continuing radio source.
Reading an entry
The reader obtains the location from FileN and uses TitleN for its description. Replacing “Opening song” with a new title changes how the entry is displayed, not what plays. Replacing File1 changes its destination even if the visible title remains unchanged.
For a local relative path, the playlist's location supplies the base relationship. Keeping the playlist and its referenced Music folder together preserves that relationship when the collection moves. A remote location instead needs the relevant network access each time playback obtains it.
A conversion to M3U writes the locations in that format's sequence and translates useful titles or lengths. Renaming .pls to .m3u does not perform this parse-and-write operation.
PLS is useful to recognize when a media shortcut opens in a desktop player but is mistaken for a saved song. The contents of FileN identify the actual source; its availability and format can then be examined separately from the playlist text.