The key data structures in the core client are as follows.
Basic types:
PROJECT APP FILE_INFO APP_VERSION IO_FILE_DESC WORKUNIT RESULT
ACCOUNTSContains a vector of PROJECTs, summarizing the accounts file.
CLIENT_STATE
Contains vectors of all the basic types. These are crossed-linked with pointers; for example, APP_VERSION has a pointer to FILE_INFO. Also contains FSM sets for network connections, HTTP operations, file transfers, and active tasks.