> 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/r/random_number_generator_device.md).

# Random number generator device

```ruby
func urandom() {
    static device = %f'/dev/urandom'

    device.open('<:raw', \var fh, \var err) ->
        || die "Can't open `#{device}': #{err}"

    fh.sysread(\var noise, 4)
    'L'.unpack(noise)
}

say urandom()    # sample: 1989353410
```