How clear positional parameter

[uzel]

Hello,

I would like done the following functionality.
At launching time
1) If argument is added to the script-name, argument is used as variable via $1 positional parameter.
2) If no argument is added to the script-name, argument is prompted and read via read v1? command.

It does not work because if option 1) is used first $1 positional parameter is always present, so case 2 appears only if "" is passed as argument

shell ksh

f1=$1
echo "v1: $1"
if [ -z "$f1" ]
then
read f1?"Enter filename: "
echo "file: $f1"
read f2?"output filename : "
else
f2=$2
fi

unix > . rvr*h aaa
v1: aaa
unix > . rvr*h
v1: aaa
unix > echo $1
aaa
unix >
unix > . rvr*h ""
v1:
Enter filename: bb
file: bb
output filename :
unix > echo $1

Do you have any idea to solve it?

Thanks in advance,

 

[feherke]

Hi

As far as I understand it, I would do it like this :

[ "$1" ] && f1="$1" || read f1?"Enter filename: "
echo "in file: $f1"

[ "$2" ] && f2="$2" || read f2?"output filename : "
echo "out file: $f2"

Feherke.

http://rootshell.be/~feherke/

 

[feherke]

Hi

How clear positional parameter

Maybe you would like to read about [tt]shift[/tt] in you man [tt]ksh[/tt]...

Feherke.

http://rootshell.be/~feherke/