R使用system（）返回错误

Question

我正在尝试了解如何从system()

捕获错误消息

EX：

> res <- system("ls home",intern=TRUE)
ls: cannot access home: No such file or directory
Warning message:
running command 'ls home' had status 2 
> res
character(0)
attr(,"status")
[1] 2

有没有办法在res中捕获“ls：无法访问主页：没有这样的文件或目录”？

Answer 1

尝试这样，即重定向stderr数据

res <- system("ls home 2>&1",intern=TRUE)

将导致

[1] "ls: home: No such file or directory"
attr(,"status")
[1] 1