read.table并删除最后几行（R）

Question

我正在尝试将内容从文本文件转换为R中的数据帧。我想跳过前三行，然后仅使用read.table读取直到*End以上的行，如下所示：

df <- read.table("file.txt", sep = ",", dec = ".", skip = 3, nrows = length("file.txt")-2)

但我收到此错误：

Error in scan(file = file, what = what, sep = sep, quote = quote, dec = dec,  : 
line 8 did not have 4 elements

数据如下：

*Keyword
*Node
$ Node,X,Y,Z
1,977201.91822656,3678881.46362572,0
2,977200.22079647,3678888.57347347,0
3,977198.87254619,3678898.82239956,0
4,977191.95056633,3679152.85114021,0
*End