diff --git a/cmd/main-server.go b/cmd/main-server.go
index 20d44fbd1..a177f7e9d 100644
--- a/cmd/main-server.go
+++ b/cmd/main-server.go
@@ -85,7 +85,8 @@ func MakeWSState(clientId string) (*WSState, error) {
 	rtn.ClientId = clientId
 	rtn.ConnectTime = time.Now()
 	rtn.PacketCh = make(chan packet.PacketType, WSStatePacketChSize)
-	rtn.Tailer, err = cmdtail.MakeTailer(rtn.PacketCh)
+	chSender := packet.MakeChannelPacketSender(rtn.PacketCh)
+	rtn.Tailer, err = cmdtail.MakeTailer(chSender)
 	if err != nil {
 		return nil, err
 	}
@@ -166,7 +167,7 @@ type MShellProc struct {
 	Lock        *sync.Mutex
 	Cmd         *exec.Cmd
 	Input       *packet.PacketSender
-	Output      chan packet.PacketType
+	Output      *packet.PacketParser
 	Local       bool
 	DoneCh      chan bool
 	CurDir      string
@@ -271,17 +272,14 @@ func writeToFifo(fifoName string, data []byte) error {
 }
 
 func sendCmdInput(pk *packet.InputPacketType) error {
-	var err error
-	if _, err = uuid.Parse(pk.SessionId); err != nil {
-		return fmt.Errorf("invalid sessionid '%s': %w", pk.SessionId, err)
-	}
-	if _, err = uuid.Parse(pk.CmdId); err != nil {
-		return fmt.Errorf("invalid cmdid '%s': %w", pk.CmdId, err)
+	err := pk.CK.Validate("input packet")
+	if err != nil {
+		return err
 	}
 	if len(pk.InputData) > MaxInputDataSize {
 		return fmt.Errorf("input data size too large, len=%d (max=%d)", len(pk.InputData), MaxInputDataSize)
 	}
-	fileNames, err := base.GetCommandFileNames(pk.SessionId, pk.CmdId)
+	fileNames, err := base.GetCommandFileNames(pk.CK)
 	if err != nil {
 		return err
 	}
@@ -405,8 +403,7 @@ func HandleRunCommand(w http.ResponseWriter, r *http.Request) {
 	rtnLine := sstore.MakeNewLineCmd(params.SessionId, params.WindowId)
 	rtnLine.CmdText = commandStr
 	runPacket := packet.MakeRunPacket()
-	runPacket.SessionId = params.SessionId
-	runPacket.CmdId = rtnLine.CmdId
+	runPacket.CK = base.MakeCommandKey(params.SessionId, rtnLine.CmdId)
 	runPacket.Cwd = ""
 	runPacket.Env = nil
 	runPacket.Command = commandStr
@@ -416,8 +413,7 @@ func HandleRunCommand(w http.ResponseWriter, r *http.Request) {
 		GlobalMShellProc.Input.SendPacket(runPacket)
 		if !GlobalMShellProc.Local {
 			getPacket := packet.MakeGetCmdPacket()
-			getPacket.SessionId = runPacket.SessionId
-			getPacket.CmdId = runPacket.CmdId
+			getPacket.CK = runPacket.CK
 			getPacket.Tail = true
 			GlobalMShellProc.Input.SendPacket(getPacket)
 		}
@@ -503,7 +499,10 @@ func HandleRunCommand(w http.ResponseWriter, r *http.Request) {
 //
 
 func LaunchMShell() (*MShellProc, error) {
-	msPath := base.GetMShellPath()
+	msPath, err := base.GetMShellPath()
+	if err != nil {
+		return nil, err
+	}
 	ecmd := exec.Command(msPath)
 	inputWriter, err := ecmd.StdinPipe()
 	if err != nil {
@@ -513,13 +512,13 @@ func LaunchMShell() (*MShellProc, error) {
 	if err != nil {
 		return nil, err
 	}
-	ecmd.Stderr = ecmd.Stdout // /dev/null
+	ecmd.Stderr = ecmd.Stdout
 	err = ecmd.Start()
 	if err != nil {
 		return nil, err
 	}
 	rtn := &MShellProc{Lock: &sync.Mutex{}, Local: true, Cmd: ecmd}
-	rtn.Output = packet.PacketParser(outputReader)
+	rtn.Output = packet.MakePacketParser(outputReader)
 	rtn.Input = packet.MakePacketSender(inputWriter)
 	rtn.RpcMap = make(map[string]*RpcEntry)
 	rtn.DoneCh = make(chan bool)
@@ -559,7 +558,7 @@ func (runner *MShellProc) PacketRpc(pk packet.RpcPacketType, timeout time.Durati
 }
 
 func (runner *MShellProc) ProcessPackets() {
-	for pk := range runner.Output {
+	for pk := range runner.Output.MainCh {
 		if rpcPk, ok := pk.(packet.RpcPacketType); ok {
 			rpcId := rpcPk.GetPacketId()
 			runner.Lock.Lock()
@@ -576,12 +575,12 @@ func (runner *MShellProc) ProcessPackets() {
 		}
 		if pk.GetType() == packet.CmdDataPacketStr {
 			dataPacket := pk.(*packet.CmdDataPacketType)
-			fmt.Printf("cmd-data %s/%s pty=%d run=%d\n", dataPacket.SessionId, dataPacket.CmdId, len(dataPacket.PtyData), len(dataPacket.RunData))
+			fmt.Printf("cmd-data %s pty=%d run=%d\n", dataPacket.CK, len(dataPacket.PtyData), len(dataPacket.RunData))
 			continue
 		}
-		if pk.GetType() == packet.RunnerInitPacketStr {
-			initPacket := pk.(*packet.RunnerInitPacketType)
-			fmt.Printf("runner-init %s user=%s dir=%s\n", initPacket.ScHomeDir, initPacket.User, initPacket.HomeDir)
+		if pk.GetType() == packet.InitPacketStr {
+			initPacket := pk.(*packet.InitPacketType)
+			fmt.Printf("runner-init %s user=%s dir=%s\n", initPacket.MShellHomeDir, initPacket.User, initPacket.HomeDir)
 			runner.Lock.Lock()
 			runner.Initialized = true
 			runner.User = initPacket.User
diff --git a/go.mod b/go.mod
index 234a4331f..fb0ee179d 100644
--- a/go.mod
+++ b/go.mod
@@ -3,13 +3,17 @@ module github.com/scripthaus-dev/sh2-server
 go 1.17
 
 require (
-	github.com/creack/pty v1.1.18 // indirect
-	github.com/fsnotify/fsnotify v1.5.4 // indirect
-	github.com/google/uuid v1.3.0 // indirect
-	github.com/gorilla/mux v1.8.0 // indirect
-	github.com/gorilla/websocket v1.5.0 // indirect
-	golang.org/x/sys v0.0.0-20220412211240-33da011f77ad // indirect
+	github.com/google/uuid v1.3.0
+	github.com/gorilla/mux v1.8.0
+	github.com/gorilla/websocket v1.5.0
 	github.com/scripthaus-dev/mshell v0.0.0
 )
 
-replace "github.com/scripthaus-dev/mshell" v0.0.0 => /Users/mike/work/gopath/src/github.com/scripthaus-dev/mshell/
+require (
+	github.com/alessio/shellescape v1.4.1 // indirect
+	github.com/creack/pty v1.1.18 // indirect
+	github.com/fsnotify/fsnotify v1.5.4 // indirect
+	golang.org/x/sys v0.0.0-20220412211240-33da011f77ad // indirect
+)
+
+replace github.com/scripthaus-dev/mshell v0.0.0 => /Users/mike/work/gopath/src/github.com/scripthaus-dev/mshell/
diff --git a/go.sum b/go.sum
index a1b065d43..e0a22d41c 100644
--- a/go.sum
+++ b/go.sum
@@ -1,3 +1,5 @@
+github.com/alessio/shellescape v1.4.1 h1:V7yhSDDn8LP4lc4jS8pFkt0zCnzVJlG5JXy9BVKJUX0=
+github.com/alessio/shellescape v1.4.1/go.mod h1:PZAiSCk0LJaZkiCSkPv8qIobYglO3FPpyFjDCtHLS30=
 github.com/creack/pty v1.1.18 h1:n56/Zwd5o6whRC5PMGretI4IdRLlmBXYNjScPaBgsbY=
 github.com/creack/pty v1.1.18/go.mod h1:MOBLtS5ELjhRRrroQr9kyvTxUAFNvYEK993ew/Vr4O4=
 github.com/fsnotify/fsnotify v1.5.4 h1:jRbGcIw6P2Meqdwuo0H1p6JVLbL5DHKAKlYndzMwVZI=
diff --git a/pkg/scbase/scbase.go b/pkg/scbase/scbase.go
new file mode 100644
index 000000000..830903b20
--- /dev/null
+++ b/pkg/scbase/scbase.go
@@ -0,0 +1,21 @@
+package scbase
+
+import (
+	"os"
+	"path"
+)
+
+const HomeVarName = "HOME"
+const ScHomeVarName = "SCRIPTHAUS_HOME"
+
+func GetScHomeDir() string {
+	scHome := os.Getenv(ScHomeVarName)
+	if scHome == "" {
+		homeVar := os.Getenv(HomeVarName)
+		if homeVar == "" {
+			homeVar = "/"
+		}
+		scHome = path.Join(homeVar, "scripthaus")
+	}
+	return scHome
+}
diff --git a/pkg/sstore/sstore.go b/pkg/sstore/sstore.go
index ddbbc10c8..8ed346223 100644
--- a/pkg/sstore/sstore.go
+++ b/pkg/sstore/sstore.go
@@ -1,10 +1,12 @@
 package sstore
 
 import (
+	"path"
 	"sync"
 	"time"
 
 	"github.com/google/uuid"
+	"github.com/scripthaus-dev/sh2-server/pkg/scbase"
 )
 
 var NextLineId = 10
@@ -12,6 +14,12 @@ var NextLineLock = &sync.Mutex{}
 
 const LineTypeCmd = "cmd"
 const LineTypeText = "text"
+const DBFileName = "scripthaus.db"
+
+func GetSessionDBName(sessionId string) string {
+	scHome := scbase.GetScHomeDir()
+	return path.Join(scHome, DBFileName)
+}
 
 type SessionType struct {
 	SessionId string `json:"sessionid"`