diff --git a/shellbox.tcl b/shellbox.tcl
index 241301c..007440a 100755
--- a/shellbox.tcl
+++ b/shellbox.tcl
@@ -23,13 +23,19 @@
 #    kill terminates the shell
 #
 
-set version {$Id: shellbox.tcl,v 1.1 2002/10/23 08:50:50 zimoch Exp $}
+set version {$Id: shellbox.tcl,v 1.2 2002/10/23 09:22:46 zimoch Exp $}
 
 proc createServer {port {paranoid 0}} {
-    if $paranoid {
-        socket -server connectionHandler -myaddr localhost $port
-    } else {
-        socket -server connectionHandler $port
+    if [catch {
+        if $paranoid {
+            socket -server connectionHandler -myaddr localhost $port
+        } else {
+            socket -server connectionHandler $port
+        }
+    } msg] {
+        puts stderr "Can't install server on port $port"
+        puts stderr $msg
+        exit 2
     }
     puts "server started on port $port"
 }
@@ -124,7 +130,12 @@ proc getClientlist {} {
 proc startProgram {} {
     global command pipe
     catch {close $pipe}
-    set pipe [open "|$command" RDWR]
+    if [catch {
+        set pipe [open "|$command" RDWR]
+    } msg] {
+        puts stderr $msg
+        exit 3
+    }
     fconfigure $pipe -blocking no -buffering line
     gets $pipe
     if [eof $pipe] exit
@@ -153,12 +164,12 @@ if {[lindex $argv 0] == "-paranoid"} {
 
 set port [lindex $argv 0]
 set command [lrange $argv 1 end]
-if {![string is integer $port] || [llength command] == 0} {
+if {![string is integer $port] || [llength $command] == 0} {
     puts stderr "usage: [file tail $argv0] \[-paranoid\] <port> <command> \[args\]"
     exit 1
 }
 
-createServer $port $paranoid
 startProgram
+createServer $port $paranoid
 vwait forever