I am looking for a better way to retrieve a systems uptime. My current method works, but I feel like things can be done better.
def uptime_range
days_up = `uptime | awk {'print$3'}`.chomp.to_i
hours_up = `uptime | awk {'print$5'}`.delete(',').chomp
seconds_up = time_to_seconds(days_up,hours_up)
started = Time.now - seconds_up
"#{started.strftime('%Y.%m.%d.%H.%M')}-#{Time.now.strftime('%Y.%m.%d.%H.%M')}"
end
On linux systems you can open /proc/uptime and read seconds since the machine booted.
def started
Time.now - IO.read('/proc/uptime').split[0].to_f
end
Edit: changed to_i to to_f. With to_i, the value of started when displayed as a string or integer is more likely to vary, especially if the boot time was close to the middle of a second rather than at the beginning or end of a second.
You could check the sysinfo gem. It should give system-independent access to the uptime data.
A rubygem called linux_stat can do that pretty well:
require 'linux_stat'
LinuxStat::OS.uptime
=> {:hour=>40, :minute=>46, :second=>19.75}
Code copied from here.
But if you don't feel like using another gem for this trivial task, you can do this:
uptime = IO.read('/proc/uptime').to_f
uptime_i = uptime.to_i
puts({
hour: uptime_i / 3600,
minute: uptime_i % 3600 / 60,
second: uptime.%(3600).%(60).round(2)
})
Which prints:
{:hour=>0, :minute=>39, :second=>54.89}