#! /bin/sh
#
# $TOOLS/replpath
#
# Replaces any old reference of the environment variable (whose name is passed
# in $1) in the PATH with a new definition (specified in the $2 parameter).
# (The old definition must be contained in the substitution of the $1 param).
#
# If there is no matching old reference of the environment variable in the
# PATH, the new definition (specified in the $2 and $3 parameters) will be
# appended to the existing PATH.
#
# Defines the $1 environment variable name having the new value specified in
# the $2 parameter.
#
# The calling script must execute this in the context of the parent's shell,
# so the environment variables that are defined are accessible by the parent.
# Example:
#	set ORACLE_HOME $NEWORACLE_HOME /bin
#	. $TOOLS/replpath
#
#  =====> Note that this will change the parent's $1, $2, and $3 variables.
#
# Last Change 02/20/97 by Brian Lomasky to include calling example.
# Last Change 02/17/97 by Brian Lomasky to rename replace_path to replpath.
# Last Change 06/19/96 by Brian Lomasky to include $3 param and surrounding
#					colons in the PATH specification, to
#					fix problem when $ORACLE_HOME translates
#					to a subset of the $DBA or $TOOLS
#					emnvironment variables
set +u				# Do not treat unset variables as an error
OLDVAR=`eval echo \\$"$1"`	# Get the substitution of the substituted $1
if [ "$3" != "" ]
then
	P3=$3
else
	P3=""
fi
set -u				# Treat unset variables as an error
case "$OLDVAR" in
	"")	OLDVAR=PLUGH ;;	# This makes it so that null OLDVAR can't match
esac				# anything in next case statement
case "$PATH" in
	*:$OLDVAR$P3:*)
		PATH=`echo $PATH|sed "s;:$OLDVAR$P3:;:$2$P3:;g"`;;#Old match?
	*:$2$P3:*)	;;			# If already the new definition?
	*:)		PATH=${PATH}$2$P3: ;;	# If path ends in a colon?
	"")		PATH=$2$P3: ;;		# If path is null?
	*)		PATH=$PATH:$2$P3: ;;	# If none of the above?
esac
export PATH 
eval $1=$2					# Define the new environment var