char ........... Builtin basic type unsigned char .. Builtin basic type short .......... Builtin basic type unsigned short . Builtin basic type int ............ Builtin basic type unsigned int ... Builtin basic type long ........... Builtin basic type unsigned long .. Builtin basic type float .......... Builtin basic type double ......... Builtin basic type void ........... Builtin basic type Char_t ......... Signed Character 1 byte UChar_t ........ Unsigned Character 1 byte Short_t ........ Signed Short integer 2 bytes UShort_t ....... Unsigned Short integer 2 bytes Int_t .......... Signed integer 4 bytes UInt_t ......... Unsigned integer 4 bytes Seek_t ......... File pointer Long_t ......... Signed long integer 8 bytes ULong_t ........ Unsigned long integer 8 bytes Float_t ........ Float 4 bytes Double_t ....... Float 8 bytes Text_t ......... General string Bool_t ......... Boolean (0=false, 1=true) Byte_t ......... Byte (8 bits) Version_t ...... Class version identifier Option_t ....... Option string Ssiz_t ......... String size Real_t ......... TVector and TMatrix element type VoidFuncPtr_t .. pointer to void function Axis_t ......... Axis values type Stat_t ......... Statistics type TSeqCol ........ Statistics type Font_t ......... Font number Style_t ........ Style number Marker_t ....... Marker number Width_t ........ Line width Color_t ........ Color number SCoord_t ....... Screen coordinates Coord_t ........ Pad world coordinates Angle_t ........ Graphics angle Size_t ......... Attribute size Size3D ......... Attribute size Handle_t ....... Generic resource handle Display_t ...... Display handle Window_t ....... Window handle Pixmap_t ....... Pixmap handle Drawable_t ..... Drawable handle Colormap_t ..... Colormap handle Cursor_t ....... Cursor handle FontH_t ........ Font handle (as opposed to Font_t which is an index) KeySym_t ....... Key symbol handle Atom_t ......... WM token GContext_t ..... Graphics context handle (or pointer, needs to be long) FontStruct_t ... Pointer to font structure Mask_t ......... Structure mask type Time_t ......... Event time size_t ......... Statistics type SigHandler_t ... Event time istringstream .. Statistics type