A PIF file consists of information used to determine how an MS-DOS-based program should run. It can also be used as a shortcut of an executable file, and is commonly created when the user creates a shortcut to a DOS program or update the properties of a program. Microsoft Windows recognize the PIF files as executable programs and it can be run as other DOS based programs. The PIF files are not commonly used today in software due to the absence of DOS applications.
PIF file format
The PIF file basically consists of just one block of data storing the parameters required to execute under the TopView. For switches like whether or not the window should be turned off when the program ends, the fields for the window title include the maximum and minimum amount of RAM and bitmaps. The developers faced the problem that there were additional switches that did not apply to TopView, when the system was adapted for use under Windows. Instead of incorporating the new switches to the end of the file, they create the file as a database file that containing any number of entries. In this way the file consisted of a number of header areas describing what operating system should read the section, and an offset to the next section. Systems will read down the list until they found the most appropriate one. Therefore, this theory left a problem of backward compatibility. The file was finally re-arranged with the first header appearing after the starting data, which left the first 253 bytes of the file in the same format as before.