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# 1  
Old 11-14-2010
Question about getopts
I am trying to use the finction getopts in script.

From what I understand this can be an example for using:
Code:
while getopt "p:rvt:" 
do 
         case  
                  p)
                       echo "$OPTARG"
                        ;;
                   r)
                       echo "example"
                       ;;
                        
                   v)
                       echo "example "
                       ;;
                   t)
                        echo  "$OPTARG
                       ;;
             esac
done

Now I understand that if there are : after the letter then it mean that it expect argument when this letter appear.

I want to know how can I handle a case in which the user send none of the parameters above.
I mean for example when he did not write "-p","-r","-v","-t"
# 2  
Old 11-14-2010
My preferred way to handle this is to first include a ':' as the first character in getopts...

Code:
while getopts ":dhqTv" OPT                              # While there is a command line option

This tells getopts not to print an error message when an unknown option is used.

Then, you have to provide your own message when an unknown option appears, use '?' in the case statement:

Code:
      ?)   print_status_message "ERROR: Unknown flag encountered.\n" ERROR
           print_options
           exit -1
           ;;

If you omit the first ':' the output is like:

Code:
root@ms:/home/unxsa/bin>./new_script_header.ksh93.getopts.unix -k

./new_script_header.ksh93.getopts.unix: -k: unknown option.

ERROR: Unknown flag encountered.

This User Gave Thanks to purdym For This Post:
programAngel
# 3  
Old 11-15-2010
Quote:
Originally Posted by purdym
My preferred way to handle this is to first include a ':' as the first character in getopts...

Code:
while getopts ":dhqTv" OPT                              # While there is a command line option

This tells getopts not to print an error message when an unknown option is used.

Then, you have to provide your own message when an unknown option appears, use '?' in the case statement:

Code:
      ?)   print_status_message "ERROR: Unknown flag encountered.\n" ERROR
           print_options
           exit -1
           ;;

If you omit the first ':' the output is like:

Code:
root@ms:/home/unxsa/bin>./new_script_header.ksh93.getopts.unix -k

./new_script_header.ksh93.getopts.unix: -k: unknown option.

ERROR: Unknown flag encountered.

thanks, but do you handle case in which he choose no option at all and you want to send error message for this?

Because I want to write a script that when the user give no argument at all, s/he will get error message.
# 4  
Old 11-15-2010
Try something like:

Code:
print_options ()
{
   cat <<EOF

   Usage:${PROGRAM_NAME##*/}

   Optional Parameters:
           [[-d] [-v] | [-q]]

EOF
exit 0

}

...

###################################################################################
# this short curcuit is needed for when no parameters are given
###################################################################################
if [[ $1 == "" ]]
then
   print_options

fi

...

while getopts ":dhqTv" OPT                              # While there is a command line option
do
   case $OPT in
      d)   DEBUG_STRING=" -d "                                  # this is used to pass this flag to another script
           let "DEBUG += 1"
           (( $DEBUG >= 2 )) && print_status_message "DEBUG: DEBUG=$DEBUG" DEBUG
           dFLAG=$TRUE
           (( $DEBUG >= 2 )) && print_status_message "DEBUG: dFLAG=${TFSTATUS[$dFLAG]}" DEBUG
           ;;

      h)   print_options;;

      q)   QUIET_STRING=" -q "                                  # this is used to pass this flag to another script
           QUIET=$TRUE
           qFLAG=$TRUE
           (( $DEBUG >= 2 )) && print_status_message "DEBUG: qFLAG=${TFSTATUS[$aFLAG]}" DEBUG
           ;;

      T)   TESTING_STRING=" -T "                                # this is used to pass this flag to another script
           TESTING=$TRUE
           TFLAG=$TRUE
           (( $DEBUG >= 2 )) && print_status_message "DEBUG: TFLAG=${TFSTATUS[$TFLAG]}" DEBUG
           ;;

      v)   VERBOSE_STRING=" -v "                                # this is used to pass this flag to another script
           let "VERBOSE += 1"
           (( $DEBUG >= 2 )) && print_status_message "DEBUG: VERBOSE=$VERBOSE" DEBUG
           vFLAG=$TRUE
           (( $DEBUG >= 2 )) && print_status_message "DEBUG: vFLAG=${TFSTATUS[$vFLAG]}" DEBUG
           ;;

      ?)   print_status_message "ERROR: Unknown flag encountered.\n" ERROR
           print_options
           exit -1
           ;;

   esac
done                                            # end -

This User Gave Thanks to purdym For This Post:
programAngel
# 5  
Old 11-15-2010
Never been a big fan of getopt in KSH, its very limited. What happens if
you have an option that you want to use the same letter for?

For example, db_id and db_password. You can't use -d for both of them right.

Therefore, I take advantage of KSH and do something like this that lets
you pass in more descriptive option names. Note, case does not make a
difference if you code like this.

Code:
 
while(($#))
do
   case $1 in
       -+([dD]*(b_id|B_ID)))
         shift
         DB_ID=$1
         ;;
       -+([dD]*(b_pass|B_PASS)))
         shift
         DB_PASS=$1
         ;;
    -+([fF]*(lag|LAG)))
          shift
          let flag_passed=1
         ;;
       -+([iI]*(nfo|NFO)))
         usage
         return 0
         ;;
      *)
         shift ;;
   esac
done

This allows you to call your script like this

script-name -db_id xxx -db_password mypassword parm1 parm2 .....

Note if you don't want to pass a variable and set a flag only look at -flag
This User Gave Thanks to BeefStu For This Post:
programAngel
# 6  
Old 11-17-2010
thank you both.

However I am not sure it solve my problem but I think I don't explain myself good enough.

I will come back with a better specification of the problem.
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