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Modem INF File Structure

This topic summarizes the general structure and content of Windows INF file sections as they are commonly used in modem INF files. For more information about the general structure and content of Windows INF files, see General Syntax Rules for INF Files.

An INF file is composed of sections. The sample modem INF files that were included in the Driver Development Kit (DDK) are organized as follows:

  • Beginning--sections that define modem IDs

  • Middle--sections that support modem-specific commands and voice modem commands

  • Near the end--modem responses

  • End--Strings section

The following example includes three INF file sections:

%Mfg% = Models
%Modem1% = Modem1, SERENUM\MSFT5600
%Modem2% = Modem2, PCMCIA\Microsoft_56K_Plug-Play\AA1111-MSFT
; This section lists strings that are used by the modem program in Control Panel
; and the Install New Modem wizard. For example,
; Modem1 will appear as "Microsoft 56K External Data Fax Modem."
ClassName = "Modem"
Mfg = "Microsoft"
Modem1 = "Microsoft 56K External Data Fax Modem"
Modem2 = "Microsoft PCMCIA Fax-Modem"

The INF file sections that are commonly used in a modem INF file are listed in the following table:

INF file section DescriptionComments

INF Version Section

Contains the standard header for all INF files.

Every INF file must have a header section named [Version].

INF Manufacturer Section

Lists the names of manufacturers and the names of the corresponding Models sections.

Every INF file must have a [Manufacturer] section.

INF Models Section

Identifies the DDInstall sections for each device installed by the INF file, and specifies the modem IDs for each modem.

Every INF file must have a Models section.

INF DDInstall Section

Identifies other sections in the INF file that describe the resource requirements of a device and add entries to the registry, copy files, and so on.

Every INF file must have at least one DDInstall section. Generally one for each modem model the INF file is capable of installing.

INF AddReg Directive

Identifies add-registry-sections that add subkeys or value names to the registry, while optionally setting their values.

Contains most of the information in a modem INF file.

INF ControlFlags Section

Provides limited control over UI displays and events during device installation.

Can be used to prevent the names of modems from being displayed in a list of modems the user may choose to install.

INF CopyFiles Directive

Identifies sections that name the files copied from the source disks to the destination directories during device installation.

Required if your modem requires driver files to be installed in addition to the INF file.

INF DelReg Directive

Identifies sections that delete subkeys or value names from the registry.

Could be used in the uninstall part of your INF file.

INF SourceDisksNames Section

Identifies and names the disks that are the source of files that are copied to the hard disk during installation.

Required to install the INF file from disks.

INF SourceDisksFiles Section

Identifies the files that are on each of the installation disks.

Required to install the INF file from disks.

INF Strings Section

Defines one or more names that represent a string of displayable characters.

Every INF file has a [Strings] section.




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