Validating month value in shell script

Shell Programming and Scripting
1

Hi,

the below script is to get & check the correct values for minutes (0-59) that is inputed by user :

printf "$FBOLD\nPlease enter the minutes (0-59): $FREG"
        read MIN

        case "$MIN" in
        [0-9]|[0-5][0-9]) break 2;;
          *) 
        echo ""
     echo "Invalid minutes, please try again.";;
        esac

How to give the same range for day of month (1-31) and for month (1-12) and hour (0-23) ???

Also, after getting user input, how to get it displayed as below :

Cronjob scheduled on "month day_of_month day_of_week hour minute "

With Regards

2

Somrthing like this,

printf "$FBOLD\nPlease enter the minutes (0-59): $FREG"
read MIN

case "$MIN" in
[0-9]|[0-5][0-9]) echo "valid min $MIN"; break 2;;
*)
echo ""
echo "Invalid minutes, please try again.";;
esac

printf "$FBOLD\nPlease enter the month (0-12): $FREG"
read MON

case "$MON" in
0[1-9]|[0-9]|1[012]) echo "valid month $MON";break 2;;
*)
echo ""
echo "Invalid month, please try again.";;
esac

printf "$FBOLD\nPlease enter the day (0-31): $FREG"
read DAY

case "$DAY" in
0[1-9]|[0-9]|[12][0-9]|3[01]) echo "valid Day $DAY";break 2;;
*)
echo ""
echo "Invalid day, please try again.";;
esac

printf "$FBOLD\nPlease enter the hr (0-23): $FREG"
read HR

case "$HR" in
0[1-9]|[0-9]|1[0-9]|2[0123]) echo "valid hour $HR";break 2;;
*)
echo ""
echo "Invalid hour, please try again.";;
esac

y=`date '+%Y'`
day_of_week=`date -d $MON/$DAY/$y '+%u'`

echo "Cronjob scheduled on $MON $DAY $day_of_week $HR $MIN"
3

Hi,

I checked the range values for month, but its not accepting 19 or 29 etc.

actually it should accept the values from 1 to 31 only.

With Regards

4

Hi, I think You can let the date command do the work for You. If it's a valid date, it will echo the "Cronjob... " line, if it's an invalid date, You will get an error, like

Like this:

echo -n Please enter MONTH DAY HOUR MINUTE :
read MONTH DAY HOUR MINUTE
date -d"$(date -d+%Y)${MONTH}${DAY} ${HOUR}:${MINUTE}" > /dev/null && echo "Cronjob scheduled on $MONTH $DAY $HOUR $MINUTE"

But maybe You would wish to do something more than just echo the text, then create a block of code. And You may have to adjust for the date and time format used in Your LOCALE.

Best regards,
Lakris

5

hi milink,

Slightly change in code for month and day (should not between 0-12 / 0-31)
month value should be between 1-12 and day 1-31

case "$MON" in
0[1-9]|[1-9]|1[012]) echo "valid month $MON";break 2;;
*)
echo ""
echo "Invalid month, please try again.";;
esac

printf "$FBOLD\nPlease enter the day (1-31): $FREG"
read DAY

case "$DAY" in
0[1-9]|[1-9]|[12][0-9]|3[01]) echo "valid Day $DAY";break 2;;
*)
echo ""
echo "Invalid day, please try again.";;
esac