3.6 <STDIN> as an Array

One previously seen operation that returns a different value in a list context is <STDIN>. As described earlier, <STDIN> returns the next line of input in a scalar context. However, in a list context, it returns all remaining lines up to end of file. Each line is returned as a separate element of the list. For example:

@a = <STDIN>; # read standard input in a list context

If the person running the program types three lines, then presses CTRL-D[4] (to indicate "end of file"), the array ends up with three elements. Each element will be a string that ends in a newline, corresponding to the three newline-terminated lines entered.

[4] Some systems use CTRL-Z to indicate end of file, while others use it to suspend a running process.