This could help: sh -x compare.sh '2014.1.fuel5.0-mira4' '2014.1.r1.fuel5.1-mira0' + a=2014.1.fuel5.0-mira4 + b=2014.1.r1.fuel5.1-mira0 + dpkg --compare-versions 2014.1.fuel5.0-mira4 lt 2014.1.r1.fuel5.1-mira0 + [ 0 -eq 0 ] + echo 2014.1.fuel5.0-mira4 < 2014.1.r1.fuel5.1-mira0 2014.1.fuel5.0-mira4 < 2014.1.r1.fuel5.1-mira0
This could help: fuel5.0- mira4' '2014.1. r1.fuel5. 1-mira0' 1.fuel5. 0-mira4 1.r1.fuel5. 1-mira0 fuel5.0- mira4 lt 2014.1. r1.fuel5. 1-mira0 fuel5.0- mira4 < 2014.1. r1.fuel5. 1-mira0 fuel5.0- mira4 < 2014.1. r1.fuel5. 1-mira0
sh -x compare.sh '2014.1.
+ a=2014.
+ b=2014.
+ dpkg --compare-versions 2014.1.
+ [ 0 -eq 0 ]
+ echo 2014.1.
2014.1.