The Dol file format is the main executable file format for both the GameCube and the Wii. The name presumably refers to "Dolphin", which was the GameCube's codename.
It is a simple file format consisting of a header and up to 7 loadable code sections (Text0..Text6) and up to 11 data sections (Data0..Data10). All values in the header are unsigned big-endian 32-bit values.
|0x0||0x3||4||File offset to start of Text0|
|0x04||0x1b||24||File offsets for Text1..6|
|0x1c||0x47||44||File offsets for Data0..10|
|0x48||0x4B||4||Loading address for Text0|
|0x4C||0x8F||68||Loading addresses for Text1..6, Data0..10|
|0x90||0xD7||72||Section sizes for Text0..6, Data0..10|