Here are the data structures with brief descriptions:

C_dither_mode
C_drv_entry
C_fnts_item
C_gcbitmap
C_media_size
C_media_type
C_menu
C_mn_set
C_pdlg_sub
C_prn_entry
C_prn_mode
C_prn_settings
C_prn_tray
CAESPB
CBFOBSPEC
Cbit_block
Ccicon_blk
Ccicon_data
CCOLOR_CMYK
CCOLOR_ENTRY
CCOLOR_RGB
CCOLOR_TAB
CCOLOR_TAB256
CDRV_INFO
CEVMULT_IN
CEVMULT_OUT
CEVNT
Cgraphic_rectangle
CHNDL_OBJ_args
Cicon_block
Clbox_item
Cmemory_form
CMOBLK
Cmouse_event_type
Cmouse_form
Cobjc_colorword
Cobject
Cobspecptr
Cparm_block
CPDLG_HNDL_args
CpEvntrec
Cpoint_coord
CPOPUP_INIT_args
CRECT16
CRECT32
Crgb_1000
Crshdr
CSCANX
CSET_ITEM_args
CSHELTAIL
CSHELW
CSLCT_ITEM_args
Ctext_edinfo
CTHREADINFO
Cuser_block
CUTXT_FN_args
CVDIPB
CXDO_INF
CXFNT_INFO
CXSHW_COMMAND