The disadvantages are the low data rates and a relatively long connection time. 缺点是低资料速率和一个相对较长的连接时间。
A relocatable expression denotes a value that requires relocation at link time, while an absolute expression denotes a value that requires no such relocation. 可再定位的表达式表示的值在连接时间请求再定位，而一个绝对表达式表示的值不需要再定位。
