.PIF File Format

Introduction

A .pif file tells Windows how to run an MS-DOS program: which program, what memory it wants, whether it runs in a window, and what its title is. The format started with TopView and was taken up and extended by DESQview and Windows.

Microsoft never published it. What is known comes mainly from Michael Maurice’s article in Dr. Dobb’s Journal in July 1993, which gives the layout of the first part of the file and the Windows 3.0 sections. These pages describe that, and what has been checked against 130 real PIF files. Where the meaning of a field has not been established, these pages say so. Later sections, for Windows 95 and Windows NT 4.0, are only partly understood here, and are shown as bytes.

A .pif file dropped on any page opens in the explorer. It shows the program settings and the sections of the file.

Structure

Every PIF starts with a fixed classic header of 0x171 (369) bytes. After it comes a chain of named sections. The first heading is always at 0x171 and is called MICROSOFT PIFEX; the others hold settings for each version of Windows.

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