— Function: frame-parameter frame parameter

This function returns the value of the parameter parameter (a symbol) of frame. If frame is nil, it returns the selected frame's parameter. If frame has no setting for parameter, this function returns nil.

— Function: frame-parameters &optional frame

The function frame-parameters returns an alist listing all the parameters of frame and their values. If frame is nil or omitted, this returns the selected frame's parameters

— Function: modify-frame-parameters frame alist

This function alters the parameters of frame frame based on the elements of alist. Each element of alist has the form (parm . value), where parm is a symbol naming a parameter. If you don't mention a parameter in alist, its value doesn't change. If frame is nil, it defaults to the selected frame.

— Function: set-frame-parameter frame parm value

This function sets the frame parameter parm to the specified value. If frame is nil, it defaults to the selected frame.

— Function: modify-all-frames-parameters alist

This function alters the frame parameters of all existing frames according to alist, then modifies default-frame-alist (and, if necessary, initial-frame-alist) to apply the same parameter values to frames that will be created henceforth.