Pointer:dec()

Pointer:dec()method

Decrements the Pointer memory position to one or more position, meaning it moves by the size of the data type it points to.

Return value

The function returns the decremented Pointer for convenience.

Example


local str = c.string("C FFI module")

-- Creates a Pointer to this string
local pstr = c.Pointer(str)
local inv = c.Pointer(str)

inv = inv + #str-1

for i=#str-1,0, -1 do
    -- set the inv.content (a char) from the pstr.content
    inv.content = pstr.content
    -- Print the inv pointer as a string
    print(inv)
    -- and increment the string pointer by one char position
    inv:dec();
end