PIF program settings

PIF files store Windows launch settings for DOS programs.

DIGPLAY.PIF and SETSOUND.PIF describe the corresponding sound utilities. They contain a base header, Windows 386 settings, and a Windows VMM extension.

DIGPLAY.PIF launches DigPlay.EXE with argument R212.WAV. SETSOUND.PIF launches SETSOUND.EXE without arguments. These settings belong to the audio utilities’ Windows environment. They do not control sample playback in a modern game engine. See Bundled support resources.

Overall Structure

[Base header — DOS program, directory, arguments, and display settings]
[PIFEX root — linked extension header referring to the base header]
[Extension records — headers and file-relative payloads]

The base header is 369 bytes. A base-only file has no extension chain. All multibyte integers are little-endian.

Base header

Offset	Size	Type	Name	Description
`0x00`	2	`[u8; 2]`	unknown_00	Stored header bytes
`0x02`	30	`[u8; 30]`	title	Space-padded window title
`0x20`	2	`u16`	memory_max_kb	Desired conventional memory, in KiB
`0x22`	2	`u16`	memory_min_kb	Required conventional memory, in KiB
`0x24`	63	`[u8; 63]`	program	Executable filename
`0x63`	1	`u8`	flags_63	Launch flags; bit `0x10` closes the window on exit
`0x64`	1	`u8`	start_drive	Startup drive byte
`0x65`	64	`[u8; 64]`	start_directory	Working directory
`0xA5`	64	`[u8; 64]`	parameters	Program arguments
`0xE5`	1	`u8`	video_mode	Video mode byte
`0xE6`	1	`u8`	unknown_e6	Stored byte
`0xE7`	1	`u8`	irq_low	Low interrupt vector byte
`0xE8`	1	`u8`	irq_high	High interrupt vector byte
`0xE9`	1	`u8`	rows	Screen rows
`0xEA`	1	`u8`	columns	Screen columns
`0xEB`	1	`u8`	window_y	Window Y position
`0xEC`	1	`u8`	window_x	Window X position
`0xED`	2	`u16`	unknown_ed	Stored word
`0xEF`	64	`[u8; 64]`	unknown_ef	Stored bytes
`0x12F`	64	`[u8; 64]`	unknown_12f	Stored bytes
`0x16F`	1	`u8`	flags_16f	Additional flags
`0x170`	1	`u8`	flags_170	Additional flags

Text fields end at the first NUL or their fixed field boundary. Title padding is removed when displayed. Bytes after a NUL are outside the displayed string. Text fields contain legacy character bytes. A Unicode representation depends on the OEM or Windows code page used to display them.

Extension chain

Each extension header is 22 bytes. Its offsets are absolute file positions.

Offset	Size	Type	Name	Description
`+0x00`	16	`[u8; 16]`	signature	NUL-terminated extension name
`+0x10`	2	`u16`	next_offset	Next header position; `0xFFFF` ends the chain
`+0x12`	2	`u16`	data_offset	Payload position
`+0x14`	2	`u16`	data_size	Payload size in bytes

The root header starts at 0x171. Its signature is MICROSOFT PIFEX, its payload offset is zero, and its payload size is 369. This payload is the base header. Each later extension has its own signature, payload position, and size.

Windows 386 settings

The WINDOWS 386 3.0 extension contains a 104-byte settings record. Its memory limits and arguments supersede the corresponding base fields for enhanced-mode execution.

Offset	Size	Type	Name	Description
`+0x00`	2	`u16`	memory_max_kb	Desired conventional memory
`+0x02`	2	`u16`	memory_min_kb	Required conventional memory
`+0x04`	2	`u16`	foreground_priority	Foreground scheduling priority
`+0x06`	2	`u16`	background_priority	Background scheduling priority
`+0x08`	2	`u16`	ems_max_kb	Expanded memory limit
`+0x0A`	2	`u16`	ems_min_kb	Required expanded memory
`+0x0C`	2	`u16`	xms_max_kb	Extended memory limit
`+0x0E`	2	`u16`	xms_min_kb	Required extended memory
`+0x10`	2	`u16`	option_flags	Execution options
`+0x12`	2	`u16`	memory_flags	Memory options
`+0x14`	2	`u16`	video_flags	Display options
`+0x16`	18	`[u16; 9]`	hotkey	Hotkey fields
`+0x28`	64	`[u8; 64]`	parameters	Enhanced-mode arguments

Memory sizes are in KiB. 0xFFFF is retained as the stored limit value. The WINDOWS VMM 4.0 payload occupies 428 bytes in both shipped utility files.

External References

Wine PIF structures and reader