The SourceDisksFiles section names the source files used during installation and identifies the source disks that contain the files. The source disks are listed in SourceDisksNames.
In order to allow multi-platform distribution of source files, you can construct a platform-specific SourceDisksFiles section. For example, on a MIPS platform, all setup functions that use a SourceDisksFiles section will first look for a SourceDisksFiles.Mips section. If the setup functions do not find a SourceDisksFiles.Mips section, or the specified line is not found in that section, the setup functions will use the SourceDisksFiles section. This behavior affects any setup function that directly or indirectly references a SourceDisksFiles section as part of its processing.
The suffixes are not case sensitive and can be one of the following.
[SourceDisksFiles]
filename=disk-number[,subdir][,size]
.
.
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The following example SourceDisksFiles section identifies a single source file, SRS01.x86, on the disk with the ordinal of 1.
[SourceDisksFiles]
SRS01.x86 = 1
Overview, INF File Format Reference