Problem with getopts in ksh

Brad Appleton brad at SSD.CSD.HARRIS.COM
Wed Jun 13 00:28:48 AEST 1990


Okay - thanx to the net I switched to getopts instead of getopt. I am still
having a problem though (although not quite as serious). Page 216 of the 
Korn Shell Manual states that:

    A leading ':' in <optstring> affects the behavior of getopts when
    getopts encounters an option letter not in< optstring>. If <optstring>
    begins with ':', getopts puts the letter in OPTARG and sets <name> to
    '?' for an unknown option, and sets <name> to ':' when a required option
    arguments is ommitted. Otherwise, getopts displays an error message and 
    sets <name> to '?'.

So now I have the following shellscript:

    #!/bin/ksh
    #
    # tst -- test getopts
    #
    
    options="ac:d:"
    argv="-a -b -c arg -f -d"
    
    print "Pass 1: options=$options  argv=$argv"
    
    while getopts $options OPT $argv
      do case $OPT in
        a) print "a_flag=SET" ;;
        c) print "c_flag=$OPTARG" ;;
        d) print "d_flag=$OPTARG" ;;
        *) print -u2 "invalid option $OPT" ;;
      esac
    done
    
    print "Pass 2: options=$options  argv=$argv"
    
    while getopts ":$options" OPT $argv
      do case $OPT in
        a) print "a_flag=SET" ;;
        c) print "c_flag=$OPTARG" ;;
        d) print "d_flag=$OPTARG" ;;
        :) print -u2 "$OPTARG requires an argument" ;;
        \?) print -u2 "invalid option $OPTARG" ;;
      esac
    done

Now, in pass 1, when I have an invalid option - I would expect to see
"invalid option ?" printed to the screen (unless getopts returns FALSE
for bad options syntax)

However, even if getopts does return FALSE for bad syntax, I would still 
expect the \? and : cases of pass 2 to be performed, and based on my 
output, this does not appear to be the case (the output listed below is
with the -x option turned on to enable tracing):

    + options=ac:d:
    + argv=-a -b -c arg -f -d
    + print Pass 1: options=ac:d:  argv=-a -b -c arg -f -d
    Pass 1: options=ac:d:  argv=-a -b -c arg -f -d
    + getopts ac:d: OPT -a -b -c arg -f -d
    + print a_flag=SET
    a_flag=SET
    + getopts ac:d: OPT -a -b -c arg -f -d
    tst[11]: getopts: bad option(s)
    + print Pass 2: options=ac:d:  argv=-a -b -c arg -f -d
    Pass 2: options=ac:d:  argv=-a -b -c arg -f -d
    + getopts :ac:d: OPT -a -b -c arg -f -d
    + print c_flag=arg
    c_flag=arg
    + getopts :ac:d: OPT -a -b -c arg -f -d
    + getopts :ac:d: OPT -a -b -c arg -f -d
    + print d_flag=
    d_flag=
    + getopts :ac:d: OPT -a -b -c arg -f -d
    
Am I doing something wrong (I hope so) or is this a bug in /bin/ksh on
my system? The version of ksh I am running is 11/16/88 (or at least thats
what the "what" command tells me).

advTHANXance
______________________ "And miles to go before I sleep." ______________________
 Brad Appleton           brad at ssd.csd.harris.com       Harris Computer Systems
                     ...!{uunet,novavax}!hcx1!brad     Fort Lauderdale, FL USA
~~~~~~~~~~~~~~~~~~~~ Disclaimer: I said it, not my company! ~~~~~~~~~~~~~~~~~~~



More information about the Comp.unix.questions mailing list