Bash format uptime to show days, hours, minutes

I made a universal shell script, for systems which support uptime -p like newer linux and for those that don't, like Mac OS X.

#!/bin/sh

uptime -p >/dev/null 2>&1

if [ "$?" -eq 0 ]; then
  # Supports most Linux distro
  # when the machine is up for less than '0' minutes then
  # 'uptime -p' returns ONLY 'up', so we need to set a default value
  UP_SET_OR_EMPTY=$(uptime -p | awk -F 'up ' '{print $2}')
  UP=${UP_SET_OR_EMPTY:-'less than a minute'}
else
  # Supports Mac OS X, Debian 7, etc
  UP=$(uptime | sed -E 's/^[^,]*up *//; s/mins/minutes/; s/hrs?/hours/;
  s/([[:digit:]]+):0?([[:digit:]]+)/\1 hours, \2 minutes/;
  s/^1 hours/1 hour/; s/ 1 hours/ 1 hour/;
  s/min,/minutes,/; s/ 0 minutes,/ less than a minute,/; s/ 1 minutes/ 1 minute/;
  s/  / /; s/, *[[:digit:]]* users?.*//')
fi

echo "up $UP"

Gist

Referenced John1024 answer with my own customizations.

My uptime produces output that looks like:

$ uptime
 12:49:10 up 25 days, 21:30, 28 users,  load average: 0.50, 0.66, 0.52

To convert that to your format:

$ uptime | awk -F'( |,|:)+' '{print $6,$7",",$8,"hours,",$9,"minutes."}'
25 days, 21 hours, 34 minutes.

How it works

• -F'( |,|:)+'

  awk divides its input up into fields. This tells awk to use any combination of one or more of space, comma, or colon as the field separator.

• print $6,$7",",$8,"hours,",$9,"minutes."

  This tells awk to print the sixth field and seventh fields (separated by a space) followed by a comma, the 8th field, the string hours, the ninth field, and, lastly, the string minutes..

Handling computers with short uptimes using sed

Starting from a reboot, my uptime produces output like:

 03:14:20 up 1 min,  2 users,  load average: 2.28, 1.29, 0.50
 04:12:29 up 59 min,  5 users,  load average: 0.06, 0.08, 0.48
 05:14:09 up  2:01,  5 users,  load average: 0.13, 0.10, 0.45
 03:13:19 up 1 day, 0 min,  8 users,  load average: 0.01, 0.04, 0.05
 04:13:19 up 1 day,  1:00,  8 users,  load average: 0.02, 0.05, 0.21
 12:49:10 up 25 days, 21:30, 28 users,  load average: 0.50, 0.66, 0.52

The following sed command handles these formats:

uptime | sed -E 's/^[^,]*up *//; s/, *[[:digit:]]* users.*//; s/min/minutes/; s/([[:digit:]]+):0?([[:digit:]]+)/\1 hours, \2 minutes/' 

With the above times, this produces:

1 minutes
59 minutes
2 hours, 1 minutes
1 day, 0 minutes
1 day,  1 hours, 0 minutes
25 days, 21 hours, 30 minutes

How it works

• -E turns on extended regular expression syntax. (On older GNU seds, use -r in place of -E)

• s/^[^,]*up *//

  This substitutes command removes all text up to up.

• s/, *[[:digit:]]* users.*//

  This substitute command removes the user count and all text which follows it.

• s/min/minutes/

  This replaces min with minutes.

• s/([[:digit:]]+):0?([[:digit:]]+)/\1 hours, \2 minutes/'

  If the line contains a time in the hh:mm format, this separates the hours from the minutes and replaces it with hh hours, mm minutes.

Handling computers with short uptimes using awk

uptime | awk -F'( |,|:)+' '{d=h=m=0; if ($7=="min") m=$6; else {if ($7~/^day/) {d=$6;h=$8;m=$9} else {h=$6;m=$7}}} {print d+0,"days,",h+0,"hours,",m+0,"minutes."}'

On the same test cases as above, this produces:

0 days, 0 hours, 1 minutes.
0 days, 0 hours, 59 minutes.
0 days, 2 hours, 1 minutes.
1 days, 0 hours, 0 minutes.
1 days, 1 hours, 0 minutes.
25 days, 21 hours, 30 minutes.

For those who prefer awk code spread out over multiple lines:

uptime | awk -F'( |,|:)+' '{
    d=h=m=0;
    if ($7=="min")
        m=$6;
    else {
        if ($7~/^day/) { d=$6; h=$8; m=$9}
        else {h=$6;m=$7}
        }
    }
    {
        print d+0,"days,",h+0,"hours,",m+0,"minutes."
    }'

Solution: In order to get the linux uptime in seconds, Go to bash and type cat /proc/uptime.Parse the first number and convert it according to your requirement.

From RedHat documentation:

This file contains information detailing how long the system has been on since its last restart. The output of /proc/uptime is quite minimal:

350735.47 234388.90

The First number is the total number of seconds the system has been up.

The Second number is how much of that time the machine has spent idle, in seconds.

Just vor completeness... what's about:

$ uptime -p
up 2 weeks, 3 days, 14 hours, 27 minutes