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"dir2dat" refers to DATs that have been automatically created based on files in an input directory. DATs generated this way are not typically useful as-is, they usually require some hand editing after creation.

igir has the ability to create these DATs with the igir dir2dat command. Example:

igir dir2dat --input <path> [--input <path>..]

dir2dat rules

igir uses the following rules when creating dir2dat DAT files:

  • A DAT file will be created for every input path.

    If multiple input paths overlap, such as:

    igir dir2dat ^
      --input "C:\ROMs" ^
      --input "C:\ROMs\NES"
    igir dir2dat \
      --input ~/ROMs/ \
      --input ~/ROMs/NES
    igir dir2dat \
      --input ~/ROMs/ \
      --input ~/ROMs/NES

    then ROMs can appear in multiple resulting dir2dat files.


    You can use the --dat-combine option to create only one DAT even when multiple input paths are provided.

  • Each input path's basename will be used for the DAT's name.

    Here are some examples:

    Input path DAT name
    --input "ROMs" ROMs
    --input "ROMs/NES" NES
    --input "ROMs/SNES/*" SNES
    --input "ROMs/SNES/**/*" SNES
  • Archive files will be treated as a single game, with every archive entry being a separate ROM.

    This is consistent with how the igir zip command works, and with what MAME expects.

  • The input file's basename (without extension) will be used for the game name.


    This will cause input files with the same basename to be grouped together!

Combining with other options

Once DATs have been generated from input files, they are processed the same as any other DAT file. That means:

Alternative tools

It is unlikely that any ROM tool, including igir, will ever meet every person's exact DAT creation needs.

SabreTools is a great tool for DAT management that offers many complex options for DAT creation, filtering, merging, and splitting.