How to Compare Those (Date) Values in Bash
I Need to Compare 2 Strings of the Following Formatting: 2013-12-31T00:00:00 2014-11-19T15:40:30 Its a Custom Datetime Format. I Tried Different Things, None...
I need to compare 2 strings of the following formatting:
2013-12-31T00:00:00
2014-11-19T15:40:30
Its a custom datetime format. I tried different things, none worked:
if [ ${val1} < ${val2} ] || [ ${val1} == ${val2} ]; then ...
or
if [ ${val1} <= ${val2} ]
or
if [[ ${val1} -el ${val2} ]]
Thanks guys!
1 Answer
Bash has its own testing syntax, where you can use > and <:
$ val1=2013-12-31T00:00:00
$ val2=2014-11-19T15:40:30
$ [[ $val1 > $val2 ]]
$ echo $?
1
$ [[ $val1 < $val2 ]]
$ echo $?
0
Alternatively you can use Unix timestamps and compare the integer values:
$ val1=$(date --date='2013-12-31T00:00:00' +%s)
$ val2=$(date --date='2014-11-19T15:40:30' +%s)
$ [ $val1 -gt $val2 ]
$ echo $?
1
$ [ $val1 -lt $val2 ]
$ echo $?
0
James Sterling reports on renewable energy developments, climate policy, ecological conservation, and green tech innovations around the globe.
