Variables starting with `o' in 321/linux

• old_mouse_x 321/linux/gl_glx.c:77
• old_mouse_y 321/linux/gl_glx.c:77
• op 321/linux/qgl_linux.c:59
• opcode 321/linux/qgl_linux.c:220
• order 321/linux/qgl_linux.c:221