Inside Macintosh: Files
The hierarchical arrangement of files and directories allows you to identify a file or directory uniquely by providing just three pieces of information: its volume reference number, its parent directory ID, and its name within that parent directory. The system software lets you specify these three items together in a file system specification record, defined by the FSSpec data type:
TYPE FSSpec = {file system specification}
RECORD
vRefNum: Integer; {volume reference number}
parID: LongInt; {directory ID of parent directory}
name: Str63; {filename or directory name}
END;
The FSSpec record provides a simple and standard format for specifying files and directories. For example, the Standard File Package procedure StandardGetFile uses an FSSpec record to return information identifying a user-selected file or folder. You can pass that specification directly to any file-manipulation routines, such as FSpOpenDF and FSpDelete , that accept FSSpec records. In addition, the Alias Manager, Edition Manager, and Finder all use FSSpec records to specify files and directories.