Translation of DCL command files

DCL is a proprietary command language supporting complex programming. Unix supports several command interpreters, called shells, therefore the user must choose among the shells the one best fitting the required needs.

In our migration activity we have translated DCL commands into Bourne shell scripts. The main feature required by the migrated scripts is the interactive inquiry of expected arguments if missing. DCL arguments are positional and have predefined names p1, p2, .., migrating to Bourne shell, we have maintained a similar convention moving arguments $1, $2, .. to $p1, $p2, ... as shown in the following fragment.

#
#-------------------------define args---------------------------------------
#
case $# in
0) echo "Type Selection File Name or NL> \c"
   read p1
   echo "Type x_y for DIST file name> \c"
   read p2
   echo "Type file type (ex. .DAT, MU1, etc.)> \c"
   read p3
   ;;
1) p1=$1
   echo "Type x_y for DIST file name> \c"
   read p2
   echo "Type file type (ex. .DAT, MU1, etc.)> \c"
   read p3
   ;;
2) p1=$1; p2=$2
   echo "Type file type (ex. .DAT, MU1, etc.)> \c"
   read p3
   ;;
3) p1=$1; p2=$2; p3=$3
   ;;
esac
echo args are: $p1 $p2 $p3

For more information about command migration check also [4].