Shell script for date manipulation

I want to do something if the date is in between 08:03 an 14:03 in a script.

but when I try

dt=`date +%H:%M`


if [ $dt -eq 08:03 ]
then
echo $dt > msize.txt
#echo "iam im 1 if"
fi

it doesn't work. This fil开发者_JS百科e is run in crontab in every minute. Please suggest something

As Rafe points out in the other answer, -eq is numeric, you need to use == to compare strings. But you said that you want to tell if the time is between two times, not exactly equal to one. In that case you should use the < operator:

if [ '08:03' \< "$dt" -a "$dt" \< '14:03']

Or more conveniently:

if [[ '08:03' < "$dt" && "$dt" < '14:03']]

Note that these operators are not specified in POSIX, but work on most shells (Bash, Korn Shell, zsh). Just beware of using them if you're using a minimal shell like Dash (which is what /bin/sh is on Ubuntu).

The -eq operator is for comparing integers, not strings. If you want to compare strings, you'll need to use ==. Try this:

if [ $dt == '08:03' ]
then
# Rest of script