Bourne Shell Scripting Assistance

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June 3rd, 2004, 09:20 PM

Tajikistanian

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Join Date: Jun 2004

Posts: 2

Time spent in forums: < 1 sec
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Bourne Shell Scripting Assistance

Hi all,

I'm relatively new to bourne shell scripting, and I'm trying to write a planner script.

Code:

#! /bin/sh 
# Option 2 
# Get date from user 
echo "Please enter day, month and year of event:" 
read date 

if [ $# -eq 3 ] 
then 
        if [ $3 -lt date '+%Y' ] 
        then 
                echo Invalid year entered. 
        else 
                if [ $2 -le `date '+%m'`] 
                then 
                        echo Invalid date entered. 
                else 
                        if [ $1 -le `date '+%d'` ] 
                        then 
                                echo Invalid month entered. 
                        else 
                                # Get hour, minute and length from user 
                                echo "Please enter hour, minute and length of event:" 
                                read time 

                                # Check that hour is valid. 
                                if [ $1 -lt 0 -a -gt 23 ] 
                                then 
                                        echo Invalid hour entered. Must be between 0 and 23 inclusive. 
                                else 
                                        if [ $2 -lt 0 -o -gt 59 ] 
                                        then 
                                                echo Invalid minute entered. Must be between 0 and 59 inclusive. 
                                        else 
                                                # Get title from user 
                                                echo "Please enter a title for your event:" 
                                                read title 
                                        fi 
                                fi 
                        fi 
                fi 
        fi 
else 
        echo Invalid number of arguments entered. 
fi

Thats what I've got so far, which is to do with adding a entry to the planner datafile (planner.txt). I'm stuck with the bit about checking that the user entered the right number of arguments. I've gathered that $# can't be used to check for the number of arguments entered via read like they can straight to the script. Can someone point me in the right direction with this?

Would also appreciate if someone could suggest any ways I could write what I've got in a better way. Seems a bit long and I'm sure there must be a better way.

Hopefully someone can help.

Also need some help with sorting the datafile for the planner. The entries are in the format:
16/08/2004 12:17 35 Some event
20/01/2005 13:25 17 some event
20/13/1900 22:00 17 some event
20/16/1925 13:15 25 some event
20/09/1986 13:56 25 some event
and I want to sort them by year, month and then day.

June 16th, 2004, 11:40 PM

Nevets

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Join Date: Apr 2004

Posts: 11

Time spent in forums: < 1 sec
Reputation Power: 0

Here are some tips that might help you out, or at least put you in the right direction:

PHP Code:


		
			
# Get date from user 

echo "Please enter day, month and year of event (DDMMYY): \c" 

read date 



day=`echo $date | cut -c1-2`

month=`echo $date | cut -c3-4`

year=`echo $date | cut -c5-6`





if [  $year -lt `date '+%Y'` -o $month -le `date '+%m'` -o $day -le `date '+%d'` ] ; then

    echo "Invalid date format"

    exit 1

else 

    # Get hour, minute and length from user 

    echo "Please enter start time of the event (hh:mm)" 

    read time 

    # do a similar cut as above

    # and validate as you like

    # if err, exit 1

    echo "Enter event duration in minutes: \c"

    read duration    

fi



# Get title from user 

echo "Please enter a title for your event:" 

read title

I find that it has also helps to wrap prompts/validations in while loops (eg. while not valid answer) so that fat fingered typing by the user doesn't cause them to start over from scratch.

June 16th, 2004, 11:43 PM

Nevets

Registered User

Join Date: Apr 2004

Posts: 11

Time spent in forums: < 1 sec
Reputation Power: 0

For your sort problem, do check out the man pages on sort
(man sort)

Some things to look for are how to set the field delimeter, in your case a "/". Then how to sort based on the 3rd, 2nd and 1st fields.

Also check out the -o swicth so you don't have to use a temp file.

Good luck.

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