diff --git a/commands/Makefile b/commands/Makefile
index 03de65826..978ccefb4 100644
--- a/commands/Makefile
+++ b/commands/Makefile
@@ -7,7 +7,7 @@ SUBDIR=	aal add_route adduser advent arp ash at autil awk \
 	binpackages binsizes bzip2 bzip2recover cal calendar \
 	cat cawf cd  cdprobe checkhier chmem \
 	chmod chown chroot ci cksum cleantmp clear cmp co \
-	comm compress cp crc cron crontab cut datasizes date \
+	comm compress cp crc cron crontab cut date \
 	dd de decomp16 DESCRIBE dev2name devsize df dhcpd \
 	dhrystone diff dirname dis88 du dumpcore easypack \
 	ed eject elle elvis env expand factor file \
diff --git a/commands/datasizes/Makefile b/commands/datasizes/Makefile
deleted file mode 100644
index 95e6110cf..000000000
--- a/commands/datasizes/Makefile
+++ /dev/null
@@ -1,4 +0,0 @@
-SCRIPTS= datasizes.sh
-MAN=
-
-.include <bsd.prog.mk>
diff --git a/commands/datasizes/datasizes.sh b/commands/datasizes/datasizes.sh
deleted file mode 100644
index 2c45a672d..000000000
--- a/commands/datasizes/datasizes.sh
+++ /dev/null
@@ -1,14 +0,0 @@
-#!/bin/sh
-
-if [ $# -ne 1 ]
-then	echo "Usage: $0 <executable>"
-	exit 1
-fi
-
-if file $1 | grep NSYM >/dev/null 2>&1; then
-  NM="gnm --radix=d"
-else
-  NM="acknm -d"
-fi
-
-$NM -n $1 | grep ' [bBdD] [^.]' | awk '{ if (lastpos) printf "%10ld kB  %s\n", ($1-lastpos)/1024, lastname; lastpos=$1; lastname=$3 }' | sort -n
diff --git a/commands/unstack/Makefile b/commands/unstack/Makefile
index 13cbdce35..9527eb335 100644
--- a/commands/unstack/Makefile
+++ b/commands/unstack/Makefile
@@ -1,4 +1,6 @@
 SCRIPTS= unstack.sh
 MAN=
 
+LINKS+=$(BINDIR)/unstack $(BINDIR)/datasizes
+
 .include <bsd.prog.mk>
diff --git a/commands/unstack/unstack.sh b/commands/unstack/unstack.sh
index 648f76092..1be8c93c4 100644
--- a/commands/unstack/unstack.sh
+++ b/commands/unstack/unstack.sh
@@ -1,26 +1,71 @@
 #!/bin/sh
 
+# Look at /usr/pkg/bin first in case there is an old nm in /usr/bin
+PATH=/usr/pkg/bin:$PATH:/usr/gnu/bin
+
+# Check usage
 if [ $# -lt 1 ]
-then	echo "Usage: $0 <executable> [0x... [0x... ] ]"
+then	echo "Usage: unstack <executable> [0x... [0x... ] ]"
+	echo "       datasizes <executable>"
 	exit 1
 fi
 
-PATH=$PATH:/usr/gnu/bin:/usr/pkg/bin
-
-if file $1 | grep NSYM >/dev/null 2>&1; then
-  NM="gnm --radix=d"
-else
-  NM="acknm -d"
-fi
+# Check invocation mode
+case "`basename $0`" in
+	datasizes)
+		mode=data
+		;;
+	unstack)
+		mode=stack
+		;;
+	*)
+		echo "Invoked as $0?"
+		exit 1
+		;;
+esac
 
+# Get executable name
 executable=$1
 shift
 
-while [ $# -gt 0 ]
-do	dec="`printf %d $1`"
-	$NM -n $executable | grep ' [Tt] [^.]' | awk '
-	  {  if($1 > '$dec') { printf "%s+0x%x\n", name, '$dec'-offset; exit }
-	     name=$3; offset=$1
-	  }'
-	shift
-done
+# gnu nm can be gnm or nm
+if which gnm >/dev/null 2>&1
+then	GNM=gnm
+else	GNM=nm
+fi
+
+# Invoke gnu nm or ack nm?
+if file $executable | grep NSYM >/dev/null 2>&1
+then	NM="$GNM --radix=d"
+else	NM="acknm -d"
+fi
+
+# Invoked as unstack?
+if [ $mode = stack ]
+then
+	while [ $# -gt 0 ]
+	do	dec="`printf %d $1`"
+		$NM -n $executable | grep ' [Tt] [^.]' | awk '
+		  {  if($1 > '$dec') { printf "%s+0x%x\n", name, '$dec'-offset; exit }
+		     name=$3; offset=$1
+		  }'
+		shift
+	done
+
+	exit 0
+fi
+
+# Invoked as datasizes?
+if [ $mode = data ]
+then
+	$NM -n $executable |
+		grep ' [bBdD] [^.]' | awk '{ if (lastpos) printf "%10ld kB  %s\n", ($1-lastpos)/1024, lastname; lastpos=$1; lastname=$3 }' | sort -n
+
+	exit 0
+fi
+
+# Can't happen.
+echo "Impossible invocation."
+
+exit 1
+