> For the complete documentation index, see [llms.txt](https://trizen.gitbook.io/sidef-lang/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://trizen.gitbook.io/sidef-lang/programming_tasks/t/take_notes_on_the_command_line.md).

# Take notes on the command line

```ruby
var file = %f'notes.txt'
 
if (ARGV.len > 0) {
    var fh = file.open_a
    fh.say(Time.local.ctime + "\n\t" + ARGV.join(" "))
    fh.close
} else {
    var fh = file.open_r
    fh && fh.each { .say }
}
```

#### Output:

```
$ sidef notes.sf Test 1
$ sidef notes.sf Test 2
$ sidef notes.sf
Sat Sep 12 00:19:36 2015
        Test 1
Sat Sep 12 00:19:37 2015
        Test 2
```