#!/bin/ksh
location=`pwd`
if [ ! -d $location/RCS ]
then
    echo "RCS directory in $location does not exist."
    echo "Therefore, desired file cannot exist here."
    echo "Either mkdir RCS in $location or change to"
    echo "appropriate directory and call hget again."
    exit 1
fi
if [ $# -ne 2 ]
then
    echo "hget: illegal usage"
    echo "Usage: hget file date (yyyy/mm/dd)"
    exit 2
fi
echo $2 | tr -d / | grep ^[12][90][0189][0-9][01][0-9][0-3][0-9]$ > /dev/null
if [ $? -ne 0 ]
then
    echo "hget: date in the wrong format"
    echo "date should be of format: yyyy/mm/dd"
    exit 3
fi
if [ -f $1 ]
then
    echo "$1 is already in $location"
    echo "hget cannot work unless $1 is checked in by RCS"
    echo "type ci $1 or remove $1 from $location"
    exit 4
fi
echo "Using RCS to retrieve most recent version of $1"
co $1 
if [ $? -ne 0 ]
then
    echo "RCS could not retrieve $1"
    echo "Make sure $1 is typed correctly and that it is"
    echo "an RCS source control file"
    exit 5
fi
echo "Using RCS to retrieve latest version of $1 on or before $2"
cp $1 .h_temp_version
ci $1
co -d$2 $1
if [ $? -ne 0 ]
then
    echo "RCS could not retrieve $1, edited before $2"
    echo "Use rlog $1 to look at revision dates."
    rm -f .h_temp_version; rm -f $1
    exit 6
fi
echo ""
echo "Showing differences since $2 in $1 using diff"
echo "Newest version is first file.  See diff for explanation"
echo ""
diff .h_temp_version $1
if [ $? -eq 0 ]
then
    echo "No changes made since $2 to $1"
    rm $1
    rm -f .h_temp_version; rm -f $1
    exit 7
else
    rm -f .h_temp_version
    rm -f $1
    exit 0
fi