为什么我无法在readLines中阅读下载的文件？我怎么读呢？
url="http://www.hkex.com.hk/chi/market/sec_tradinfo/stockcode/eisdeqty_c.htm"
txt=download.file(url,destfile="stock")
> file1=readLines("stock",encoding="big5")
Warning messages:
1: In readLines("stock", encoding = "big5") :
invalid input found on input connection 'stock'
2: In readLines("stock", encoding = "big5") :
incomplete final line found on 'stock'
> file1=readLines("stock",encoding="gbk")
Warning messages:
1: In readLines("stock", encoding = "gbk") :
invalid input found on input connection 'stock'
2: In readLines("stock", encoding = "gbk") :
incomplete final line found on 'stock'
> file1=readLines("stock",encoding="gb2132")
Warning messages:
1: In readLines("stock", encoding = "gb2132") :
invalid input found on input connection 'stock'
2: In readLines("stock", encoding = "gb2132") :
incomplete final line found on 'stock'
> file1=readLines("stock",encoding="gb18030")
Warning messages:
1: In readLines("stock", encoding = "gb18030") :
invalid input found on input connection 'stock'
2: In readLines("stock", encoding = "gb18030") :
incomplete final line found on 'stock'
该文件只包含部分内容，许多内容丢失，为什么？