If I do something like this:

```
> df <- data.frame()
> rbind(df, c("A","B","C"))
  X.A. X.B. X.C.
1    A    B    C

```

You can see the row gets added to the empty data frame. However, the columns get named automatically based on the content of the data.

This causes problems if I later want to:

```
> df <- rbind(df, c("P", "D", "Q"))

```

Is there a way to control the names of the columns that get automatically created by rbind? Or some other way to do what I'm attempting to do here?