How can I calculate minutes to the next 7:00am is, in a shell script ?

Glenn D. · 11-20-2009, 05:47 AM

How can I calculate minutes to the next 7:00am is, in a shell script ?

Example it may be 21:30 or 0:10 now and I want to find out how many minutes to the next 7:00am is ?
Can you provide a sample script to do that please ?

Thanks Glenn

indiajoe · 11-20-2009, 08:22 AM

Hi
Make a script as follows,

Code:

#!/bin/sh
hour=`date | cut -b 12-13`
minute=`date | cut -b 15-16`
if [ "$hour" -lt 7 ] ; then
hourrem=$((6 - hour))
else
hourrem=$((23 - hour + 7 ))
fi
minuterem=$((59 - minute))
hourmin=$((hourrem * 60))
Total=$((hourmin + minuterem))

echo "Remaining minutes to 7am is $Total"

-Cheers
indiajoe

#!/usr/bin/which · 11-20-2009, 10:47 AM

This will give you the time left till the next 7:00 a.m. in minutes

Code:

$ bc <<< "(( $(date -d'07:00 am' +%s) - $(date +%s) + 60*60*24 ) % (60*60*24)) / 60"

Glenn D. · 11-20-2009, 10:40 PM

Thanks for the info.
In the end I had to take account of the time zone too.

# cat ./time-test.sh
#!/bin/sh
export TZ=Australia/Sydney
date
hour=`date | cut -b 12-13`
minute=`date | cut -b 15-16`
if [ "$hour" -lt 7 ] ; then
hourrem=$((6 - hour))
else
hourrem=$((23 - hour + 7 ))
fi
minuterem=$((59 - minute))
hourmin=$((hourrem * 60))
Total=$((hourmin + minuterem))

echo "Remaining minutes to 7am is $Total"

Sample run:

# ./time-test.sh
Sat Nov 21 15:38:37 EST 2009
Remaining minutes to 7am is 921