One or more file names.
You can give more than one WAD file as the parameter:
-file primary.wad secondary.wad tertiary.wad
In addition to normal WAD files, the -file option can be used to load any type of data files, for instance PCX images. An example:
This would load the file image.pcx from the runtime directory (or, as a fallback, the data directory). When loading files in this manner, the engine will treat the file as if it was a WAD file with a single data lump (and no WAD directory). The lump gets its name from the base of the file name, which in the example's case would be IMAGE. Anyone can then refer to the data lump using that name, just as if it was included in a WAD file.
Any file loaded with the -file option can't be unloaded from memory at runtime using the unload command. This is mainly a precaution, since unloading the main WAD file of the game or any data related to it would lead to fatal errors.
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