Re: [Qemu-devel] vnc port selection

[acue <acue@i4p.de>]

[-- Attachment #1: Type: text/plain, Size: 1793 bytes --]

Anthony Liguori wrote:
> Gerd Hoffmann wrote:
>>   Hi folks,
>>
>> Xen's qemu-dm version has a '-vncunused' command line switch which asks
>> the internal vnc server to pick any unused tcp port to listen on.  The
>> actual port is communicated to the outside world via xenstore.
>>
>> I'm looking for a reasonable way to implement that functionality in
>> upstream qemu.  First, I think it shouldn't be a separate command line
>> switch but an option for the existion -vnc switch.
>
> Maybe something like a to=N option.  So you would have:
>
> -vnc localhost:0,to=10
>
> That would try from displays 0 to 10 and select the first one it could 
> attach to.
>
>>   Second, we need a
>> way to communicate the port picked which isn't xen-specific.  Obvious
>> choice is a monitor info subcommand.
>>   
>
> There's already an info vnc.  It can be added to that.
>
> Regards,
>
> Anthony Liguori
>
>> Comments?  Other suggestions?
>>
>> cheers,
>>   Gerd
>>
>>   
>
>
>
>
Hello Gerd,
Even though currently it is a bash+awk solution the algorithm could be 
of interest for you.

It works on Linux+OpenBSD+Solaris and accepts MIN and MAX value for the 
port.
An aditional seed-value is added for slowly-released ports for immediate 
access.

I use different ranges particularly in order to distinguish 
displayforwarding and
"clientforwarding".
Thus one range for local vncviewer access by OpenSSH with "-X" option, 
another for
forwarded remote vncviewer access by OpenSSH tunnels with port-forwarding.

The files are available at http:/sourceforge.net/projects/ctys with the
directory path: ctys.01_07_001b04/plugins/VNC

Arno
 

-- 
----------------------------------------------------------------------------

                   Arno-Can Uestuensoez

                www.i4p.de  / www.i4p.com


[-- Attachment #2: getFirstFreeVNCPort.Linux.awk --]
[-- Type: text/plain, Size: 1202 bytes --]

########################################################################
#
#PROJECT:      Unified Sessions Manager
#AUTHOR:       Arno-Can Uestuensoez - acue@UnifiedSessionsManager.org
#MAINTAINER:   Arno-Can Uestuensoez - acue_sf1@sourceforge.net
#SHORT:        ctys
#CALLFULLNAME: Commutate To Your Session
#LICENCE:      GPL3
#VERSION:      01_06_001a10
#
########################################################################
#
# Copyright (C) 2007 Arno-Can Uestuensoez (UnifiedSessionsManager.org)
#
########################################################################

function ptrace(inp){
    if(!d){
        print line ":" inp | "cat 1>&2"
    }
}


BEGIN{
    ptrace("awk:getFirstFreeVNCPort");
    ptrace("min ="min);
    ptrace("max ="max);
    ptrace("seed="seed);
    chk[0]="";
}

{
    gsub("^[0-9.]*:+","",$4);
}

$4>min&&$4<max{
    idx=$4-min;
    chk[idx]=$4;
}

END{
    l=max-min;
    for(i=0;i<l;i++){
        if(chk[i]==""){
            if(seed==0){break;}
            seed--;
            ptrace("skip("seed")="i);
        }
    }
    if(i<max){
        ptrace("result="i);
        printf("%d",min+i);
    }else{
        ptrace("result exceeds maximum("max")="i);
    }
}

[-- Attachment #3: getFirstFreeVNCPort.OpenBSD.awk --]
[-- Type: text/plain, Size: 1202 bytes --]

########################################################################
#
#PROJECT:      Unified Sessions Manager
#AUTHOR:       Arno-Can Uestuensoez - acue@UnifiedSessionsManager.org
#MAINTAINER:   Arno-Can Uestuensoez - acue_sf1@sourceforge.net
#SHORT:        ctys
#CALLFULLNAME: Commutate To Your Session
#LICENCE:      GPL3
#VERSION:      01_06_001a10
#
########################################################################
#
# Copyright (C) 2007 Arno-Can Uestuensoez (UnifiedSessionsManager.org)
#
########################################################################

function ptrace(inp){
    if(!d){
        print line ":" inp | "cat 1>&2"
    }
}


BEGIN{
    ptrace("awk:getFirstFreeVNCPort");
    ptrace("min ="min);
    ptrace("max ="max);
    ptrace("seed="seed);
    chk[0]="";
}

{
    gsub("^[0-9.]*:+","",$4);
}

$4>min&&$4<max{
    idx=$4-min;
    chk[idx]=$4;
}

END{
    l=max-min;
    for(i=0;i<l;i++){
        if(chk[i]==""){
            if(seed==0){break;}
            seed--;
            ptrace("skip("seed")="i);
        }
    }
    if(i<max){
        ptrace("result="i);
        printf("%d",min+i);
    }else{
        ptrace("result exceeds maximum("max")="i);
    }
}

[-- Attachment #4: getFirstFreeVNCPort.SunOS.awk --]
[-- Type: text/plain, Size: 1202 bytes --]

########################################################################
#
#PROJECT:      Unified Sessions Manager
#AUTHOR:       Arno-Can Uestuensoez - acue@UnifiedSessionsManager.org
#MAINTAINER:   Arno-Can Uestuensoez - acue_sf1@sourceforge.net
#SHORT:        ctys
#CALLFULLNAME: Commutate To Your Session
#LICENCE:      GPL3
#VERSION:      01_06_001a10
#
########################################################################
#
# Copyright (C) 2007 Arno-Can Uestuensoez (UnifiedSessionsManager.org)
#
########################################################################

function ptrace(inp){
    if(!d){
        print line ":" inp | "cat 1>&2"
    }
}


BEGIN{
    ptrace("awk:getFirstFreeVNCPort");
    ptrace("min ="min);
    ptrace("max ="max);
    ptrace("seed="seed);
    chk[0]="";
}

{
    gsub("^[0-9.]*:+","",$4);
}

$4>min&&$4<max{
    idx=$4-min;
    chk[idx]=$4;
}

END{
    l=max-min;
    for(i=0;i<l;i++){
        if(chk[i]==""){
            if(seed==0){break;}
            seed--;
            ptrace("skip("seed")="i);
        }
    }
    if(i<max){
        ptrace("result="i);
        printf("%d",min+i);
    }else{
        ptrace("result exceeds maximum("max")="i);
    }
}

[-- Attachment #5: hook --]
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#!/bin/bash

########################################################################
#
#PROJECT:      Unified Sessions Manager
#AUTHOR:       Arno-Can Uestuensoez - acue@UnifiedSessionsManager.org
#MAINTAINER:   Arno-Can Uestuensoez - acue_sf1@sourceforge.net
#SHORT:        ctys
#CALLFULLNAME: Commutate To Your Session
#LICENCE:      GPL3
#VERSION:      01_03_001b01
#
########################################################################
#
# Copyright (C) 2007 Arno-Can Uestuensoez (UnifiedSessionsManager.org)
#
########################################################################

VNC_MAGIC=VNC_GENERIC;
VNC_VERSTRING=;
VNC_STATE=DISABLED;
VNCSERVER_OPT=;
VNCVIEWER_OPT=;
VNC_PREREQ=;


export VNC_BASEPORT=${VNC_BASEPORT:-5900}

_myPKGNAME_VNC="${BASH_SOURCE}"
_myPKGVERS_VNC="01.02.001b01"
hookInfoAdd $_myPKGNAME_VNC $_myPKGVERS_VNC
_myPKGBASE_VNC="${_myPKGNAME_VNC%/hook}"


VNC_VERSTRING=${_myPKGVERS_VNC};
VNC_PREREQ="HOST-CAPABILITY:VNC-${VNC_VERSTRING}-${MYARCH}";


if [ -d "${HOME}/.ctys" -a -d "${HOME}/.ctys/vnc" ];then
    if [ -f "${HOME}/.ctys/vnc/vnc.conf.${MYOS}" ];then
	. "${HOME}/.ctys/vnc/vnc.conf.${MYOS}"
    fi
fi

if [ -d "${MYCONFPATH}" -a -d "${MYCONFPATH}/vnc" ];then
    if [ -f "${MYCONFPATH}/vnc/vnc.conf.${MYOS}" ];then
	. "${MYCONFPATH}/vnc/vnc.conf.${MYOS}"
    fi
fi



_waitcVNC=${VNC_INIT_WAITC:-2}
_waitsVNC=${VNC_INIT_WAITS:-2}



#FUNCBEG###############################################################
#NAME:
#  getFirstFreeVNCPort
#
#TYPE:
#  bash-function
#
#DESCRIPTION:
#  Gets the first free port above a given base, thus multiple regions
#  could be managed
#
#EXAMPLE:
#
#PARAMETERS:
#  $1: <MIN>
#  $2: [<MAX>]
#
#OUTPUT:
#  RETURN:
#  VALUES:
#    <first-port>
#
#FUNCEND###############################################################
function getFirstFreeVNCPort () {
    printDBG $S_LIB ${D_BULK} $LINENO $BASH_SOURCE "$FUNCNAME:CALL=<${*}>"
    local MIN=${1:-$VNC_BASEPORT};
    local MAX=$2;
    [ -z "$MAX" ]&&let MAX=MIN+1000;
    local _seed=$((RANDOM%VNCPORTSEED));
    doDebug $S_XEN  ${D_MAINT} $LINENO $BASH_SOURCE
    local D=$?

    printDBG $S_LIB ${D_BULK} $LINENO $BASH_SOURCE "$FUNCNAME:MIN=${MIN} MAX=${MAX} seed=${_seed}"
    case ${MYOS} in
	Linux)
	    local localClientAccess=`${CTYS_NETSTAT} -n -l -t|awk -v d="${D}" -v min="${MIN}" -v max="${MAX}" -v seed="${_seed}" -f ${_myPKGBASE_VNC}/getFirstFreeVNCPort.${MYOS}.awk`
	    ;;
	OpenBSD)
	    local localClientAccess=`${CTYS_NETSTAT} -n -l -t|awk -v d="${D}" -v min="${MIN}" -v max="${MAX}" -v seed="${_seed}" -f ${_myPKGBASE_VNC}/getFirstFreeVNCPort.${MYOS}.awk`
	    ;;
	SunOS)
	    local localClientAccess=`${CTYS_NETSTAT} -n -l -t|awk -v d="${D}" -v min="${MIN}" -v max="${MAX}" -v seed="${_seed}" -f ${_myPKGBASE_VNC}/getFirstFreeVNCPort.${MYOS}.awk`
	    ;;
    esac
    printDBG $S_LIB ${D_BULK} $LINENO $BASH_SOURCE "$FUNCNAME:localClientAccess=<${localClientAccess}>"
    echo -n -e "${localClientAccess}";
}

#FUNCBEG###############################################################
#NAME:
#  getFirstFreeVNCDisplay
#
#TYPE:
#  bash-function
#
#DESCRIPTION:
#  Gets the first free display above a given base, thus multiple regions
#  could be managed
#
#EXAMPLE:
#
#PARAMETERS:
#  $1: <MIN>
#  $2: [<MAX>]
#
#OUTPUT:
#  RETURN:
#  VALUES:
#    <first-port>
#
#FUNCEND###############################################################
function getFirstFreeVNCDisplay () {
    printDBG $S_LIB ${D_BULK} $LINENO $BASH_SOURCE "$FUNCNAME:CALL=<${*}>"
    local MIN=${1:-$VNC_BASEPORT};
    local MAX=$2;
    [ -z "$MAX" ]&&let MAX=VNC_PORT+1000;
    printDBG $S_LIB ${D_BULK} $LINENO $BASH_SOURCE "$FUNCNAME:MIN=${MIN} MAX=${MAX}"
    local _myPort=`getFirstFreeVNCPort ${@}`
    local _myDisplay=$((_myPort-MIN));
    printDBG $S_LIB ${D_BULK} $LINENO $BASH_SOURCE "$FUNCNAME:_myPort=<${_myPort}>"
    printDBG $S_LIB ${D_BULK} $LINENO $BASH_SOURCE "$FUNCNAME:_myDisplay=<${_myDisplay}>"
    echo -n -e "${_myDisplay}";
}


#FUNCBEG###############################################################
#NAME:
#  serverRequireVNC
#
#TYPE:
#  bash-function
#
#DESCRIPTION:
#  Reports whether a server component has to be called for the current
#  action.
#
#EXAMPLE:
#
#PARAMETERS:
# $*: ${EXECCALL}|<options-list>
#     Generally a string containing an <options-list>, where the
#     first match is choosen. So only one type option is allowed to
#     be contained.
#
#OUTPUT:
#  RETURN:
#    INPUT, where required changes for destination are set.
#  VALUES:
#    0: true, required - output is valid.
#    1: false, not required - output is not valid.
#
#FUNCEND###############################################################
function serverRequireVNC () {
    printDBG $S_VNC ${D_BULK} $LINENO $BASH_SOURCE "$FUNCNAME \$@=$@"
    local _ret=1;
    local _res=;

    local _S=`getSessionType ${*}`;_S=${_S:-$C_SESSIONTYPE};
    local _A=`getActionResulting ${*}`;
    case $_A in
	GETCLIENTPORT)
	    printDBG $S_VNC ${D_MAINT} $LINENO $BASH_SOURCE "$FUNCNAME:_res=\"${*}\""
	    printDBG $S_VNC ${D_MAINT} $LINENO $BASH_SOURCE "$FUNCNAME:_ret=\"0\""
	    echo -n "${*}";
	    return 0
	    ;;
    esac

    local _CS_SPLIT=${*};
    _CS_SPLIT=${_CS_SPLIT//CONNECTIONFORWARDING/SERVERONLY}
    _CS_SPLIT=${_CS_SPLIT//*LOCALONLY*/}
    _CS_SPLIT=${_CS_SPLIT//*CLIENTONLY*/}
    if [ -n "${_CS_SPLIT}" ];then
	_res="${_CS_SPLIT}";_ret=0;
    fi


    printDBG $S_VNC ${D_MAINT} $LINENO $BASH_SOURCE "_CS_SPLIT=\"${_CS_SPLIT}\""
    printDBG $S_VNC ${D_MAINT} $LINENO $BASH_SOURCE "_S=\"${_S}\""
    printDBG $S_VNC ${D_MAINT} $LINENO $BASH_SOURCE "_A=\"${_A}\""

    printDBG $S_VNC ${D_MAINT} $LINENO $BASH_SOURCE "$FUNCNAME:_res=\"${_res}\""
    printDBG $S_VNC ${D_MAINT} $LINENO $BASH_SOURCE "$FUNCNAME:_ret=\"${_ret}\""
    echo -n "${_res}";
    return ${_ret};  
}



#FUNCBEG###############################################################
#NAME:
#  clientRequireVNC
#
#TYPE:
#  bash-function
#
#DESCRIPTION:
#  Reports whether a client component has to be called for the current
#  action.
#
#EXAMPLE:
#
#PARAMETERS:
# $*: ${EXECCALL}|<options-list>
#     Generally a string containing an <options-list>, where the
#     first match is choosen. So only one type option is allowed to
#     be contained.
#
#OUTPUT:
#  RETURN:
#    INPUT, where required changes for destination are set.
#  VALUES:
#    0: true, required - output is valid.
#    1: false, not required - output is not valid.
#
#FUNCEND###############################################################
function clientRequireVNC () {
    printDBG $S_VNC ${D_BULK} $LINENO $BASH_SOURCE "$FUNCNAME \$@=$@"
    local _ret=1;
    local _res=;

    local _A=`getActionResulting ${*}`;

    local _S=`getSessionType ${*}`;_S=${_S:-$C_SESSIONTYPE};
    local _CS_SPLIT=${*};
    _CS_SPLIT=${_CS_SPLIT//*DISPLAYFORWARDING*/}
    _CS_SPLIT=${_CS_SPLIT//*SERVERONLY*/}
    if [ "${_CS_SPLIT}" == "${*}" ];then
	_res="${_CS_SPLIT}";_ret=0;
    fi
    printDBG $S_VNC ${D_MAINT} $LINENO $BASH_SOURCE "_CS_SPLIT=\"${_CS_SPLIT}\""
    printDBG $S_VNC ${D_MAINT} $LINENO $BASH_SOURCE "_S=\"${_S}\""
    printDBG $S_VNC ${D_MAINT} $LINENO $BASH_SOURCE "_A=\"${_A}\""

    printDBG $S_VNC ${D_MAINT} $LINENO $BASH_SOURCE "$FUNCNAME:_res=\"${_res}\""
    printDBG $S_VNC ${D_MAINT} $LINENO $BASH_SOURCE "$FUNCNAME:_ret=\"${_ret}\""
    echo -n "${_res}";
    return ${_ret};  
}






#FUNCBEG###############################################################
#NAME:
#  setVersionVNC
#
#TYPE:
#  bash-function
#
#DESCRIPTION:
#  Sets defaults and MAGIC-ID for local vmware version.
#
#EXAMPLE:
#
#PARAMETERS:
#
#
#OUTPUT:
#  GLOBALS:
#    VNC_MAGIC:  {VNC_REAL412|VNC_TIGHT129|...}
#      Value to be checked.
#
#    VMW_DEFAULTOPTS
#      Appropriate defaults.
#
#      -RealVNC  - 4.1.2 
#      -TightVNC - 1.2.9
#
#  RETURN:
#
#  VALUES:
#
#FUNCEND###############################################################
function setVersionVNC () {
    local _checkonly=;
    local _ret=0;
    if [ "$1" == "NOEXIT" ];then
	local _checkonly=1;        
    fi

    local _verstrg=;
    if [ -z "${VNCSEXE}" ];then
	ABORT=2;
	printERR $LINENO $BASH_SOURCE ${ABORT} "Missing executable for VNCserver"
	printERR $LINENO $BASH_SOURCE ${ABORT} "can not find:"
	printERR $LINENO $BASH_SOURCE ${ABORT} " -> vncserv"
	printERR $LINENO $BASH_SOURCE ${ABORT} ""
	printERR $LINENO $BASH_SOURCE ${ABORT} "Check your PATH"
	printERR $LINENO $BASH_SOURCE ${ABORT} " -> PATH=${PATH}"
	printERR $LINENO $BASH_SOURCE ${ABORT} ""
	if [ "${C_SESSIONTYPE}" == "VNC" -a -z "${_checkonly}" ];then
	    gotoHell ${ABORT}
	else
	    return ${ABORT}
	fi
	_ret=${ABORT};
    else
	local _vsexe=`${VNCSEXE} --help 2>&1|egrep '(Usage:|usage:)'`
	ABORT=2;
	if [ -n "$_vsexe" ];then
	    printDBG $S_LIB ${D_SYS} $LINENO "$BASH_SOURCE" "$FUNCNAME:`setSeverityColor TRY \"call(${VNCSEXE} --help)\"` => [ `setSeverityColor INF OK` ]"
	    _ret=0;
	else
	    printDBG $S_LIB ${D_SYS} $LINENO "$BASH_SOURCE" "$FUNCNAME:`setSeverityColor TRY \"call(${VNCSEXE} --help)\"` => [ `setSeverityColor ERR NOK` ]"
	    _ret=${ABORT};
	fi
    fi

    if [ -z "${VNCVEXE}" ];then
	ABORT=2
	printERR $LINENO $BASH_SOURCE ${ABORT} "Missing executable for VNCviewer"
	printERR $LINENO $BASH_SOURCE ${ABORT} "can not find:"
	printERR $LINENO $BASH_SOURCE ${ABORT} " -> vncviewer"
	printERR $LINENO $BASH_SOURCE ${ABORT} ""
	printERR $LINENO $BASH_SOURCE ${ABORT} "Check your PATH"
	printERR $LINENO $BASH_SOURCE ${ABORT} " -> PATH=${PATH}"
	printERR $LINENO $BASH_SOURCE ${ABORT} ""
	if [ "${C_SESSIONTYPE}" == "VNC" -a -z "${_checkonly}" ];then
	    gotoHell ${ABORT}
	else
	    return ${ABORT}
	fi
	_ret=${ABORT};
    fi


    if [ -n "`${VNCVEXE} --help 2>&1|egrep '(RealVNC)'`" ];then
#	_verstrg=`${VNCVEXE} --help 2>&1|awk '/VNC [Vv]iewer/{printf("%s\n",$5);}'`
	_verstrg=`${VNCVEXE} --help 2>&1|sed -n 's/VNC [Vv]iewer[^0-9]*\([0-9]*.[0-9]*.[0-9]*\).*/\1/p'`
	ABORT=2;
	if [ -n "$_verstrg" ];then
            _verstrg="RealVNC-${_verstrg}"
	    printDBG $S_LIB ${D_SYS} $LINENO "$BASH_SOURCE" "$FUNCNAME:`setSeverityColor TRY \"call(${VNCVEXE} -version)\"` => [ `setSeverityColor INF OK` ]"
	    _ret=0;
	else
	    printDBG $S_LIB ${D_SYS} $LINENO "$BASH_SOURCE" "$FUNCNAME:`setSeverityColor TRY \"call(${VNCVEXE} --version)\"` => [ `setSeverityColor ERR NOK` ]"
	    _ret=${ABORT};
	fi
    else
	if [ -n "`${VNCVEXE} --help 2>&1|egrep '(TightVNC)'`" ];then
	    _verstrg=`${VNCVEXE} --help 2>&1|awk -v a=${_allign} '/[vV]iewer [vV]ersion/{printf("%s\n",$4);}'`
	    ABORT=2;
	    if [ -n "$_verstrg" ];then
		_verstrg="TightVNC-${_verstrg}"
		printDBG $S_LIB ${D_SYS} $LINENO "$BASH_SOURCE" "$FUNCNAME:`setSeverityColor TRY \"call(${VNCVEXE} -version)\"` => [ `setSeverityColor INF OK` ]"
		_ret=0;
	    else
		printDBG $S_LIB ${D_SYS} $LINENO "$BASH_SOURCE" "$FUNCNAME:`setSeverityColor TRY \"call(${VNCVEXE} --version)\"` => [ `setSeverityColor ERR NOK` ]"
		_ret=${ABORT};
	    fi
	else
	    if [ -n "`${VNCVEXE} --help 2>&1|egrep '(open display:)'`" ];then
		printWNG 1 $LINENO $BASH_SOURCE 0  "DISPLAY is not available"
		printWNG 1 $LINENO $BASH_SOURCE 0  " 1. One common cause is the call of \"ssh\" without the \"-X\""
		printWNG 1 $LINENO $BASH_SOURCE 0  "    option. Even for the utilized check by \"vncviewer --help\" "
		printWNG 1 $LINENO $BASH_SOURCE 0  "    option a display is required."
  		_verstrg=GENERIC
		_ret=0;
	    else
		printWNG 1 $LINENO $BASH_SOURCE 0  "Can not evaluate version for \"which-ed\" vncviewer."
		printWNG 1 $LINENO $BASH_SOURCE 0  "."
		printWNG 1 $LINENO $BASH_SOURCE 0  " 1. One common cause is the call of \"ssh\" without the \"-X\""
		printWNG 1 $LINENO $BASH_SOURCE 0  "    option. Even for the utilized check by \"vncviewer --help\" "
		printWNG 1 $LINENO $BASH_SOURCE 0  "    option a display is required."
		printWNG 1 $LINENO $BASH_SOURCE 0  " 2. Another common cause for the initial usage is the missing "
		printWNG 1 $LINENO $BASH_SOURCE 0  "    permission \"X11Forwarding yes\" in \"/etc/ssh/sshd_conf\"."
  		_verstrg=GENERIC
		_ret=0;
	    fi
	fi
    fi

    printDBG $S_VNC ${D_BULK} $LINENO $BASH_SOURCE "VNC"
    printDBG $S_VNC ${D_BULK} $LINENO $BASH_SOURCE "  _verstrg=${_verstrg}"


    #currently somewhat restrictive to specific versions.
    case ${_verstrg} in
	"TightVNC"*)
	    VNC_MAGIC=VNCT;
	    VNC_STATE=ENABLED;
	    VNC_PREREQ="${VNC_PREREQ}%${_verstrg}-${MYARCH} vncserver,vncviewer";
	    VNCSERVER_OPT="${VNCSERVER_OPT_TightVNC}";
	    VNCVIEWER_OPT="${VNCVIEWER_OPT_TightVNC}";
	    _ret=0;
	    ;;

	"RealVNC"*)
	    VNC_MAGIC=VNCR;
	    VNC_STATE=ENABLED;
	    VNC_PREREQ="${VNC_PREREQ}%${_verstrg}-${MYARCH} vncserver,vncviewer";
            VNCSERVER_OPT="${VNCSERVER_OPT_RealVNC}";
            VNCVIEWER_OPT="${VNCVIEWER_OPT_RealVNC}";
	    _ret=0;
	    ;;

         *)
	    VNC_MAGIC=VNCG;
            VNCSERVER_OPT="${VNCSERVER_OPT_GENERIC}";
            VNCVIEWER_OPT="${VNCVIEWER_OPT_GENERIC}";
	    VNC_PREREQ="${VNC_PREREQ}%${_verstrg}-${MYARCH}";
	    _ret=2;
	    ;;
    esac
    printDBG $S_VNC ${D_BULK} $LINENO $BASH_SOURCE "VNC_MAGIC       = ${VNC_MAGIC}"
    printDBG $S_VNC ${D_BULK} $LINENO $BASH_SOURCE "VNC_VERSTRING   = ${VNC_VERSTRING}"
    printDBG $S_VNC ${D_BULK} $LINENO $BASH_SOURCE "VNC_STATE       = ${VNC_STATE}"
    printDBG $S_VNC ${D_BULK} $LINENO $BASH_SOURCE "VNC_PREREQ      = ${VNC_PREREQ}"
    printDBG $S_VNC ${D_BULK} $LINENO $BASH_SOURCE "VNCSERVER_OPT   = ${VNCSERVER_OPT}"
    printDBG $S_VNC ${D_BULK} $LINENO $BASH_SOURCE "VNCVIEWER_OPT   = ${VNCVIEWER_OPT}"
    return $_ret;
}







#FUNCBEG###############################################################
#NAME:
#  noClientServerSplitSupportedMessageVNC
#
#TYPE:
#  bash-function
#
#DESCRIPTION:
#
#EXAMPLE:
#
#PARAMETERS:
#
#OUTPUT:
#  RETURN:
#  VALUES:
#
#FUNCEND###############################################################
function noClientServerSplitSupportedMessageVNC () {
    ABORT=2
    printERR $LINENO $BASH_SOURCE ${ABORT} "Unexpected ERROR!!!"
    printERR $LINENO $BASH_SOURCE ${ABORT} "VNC perfectly supports ClientServerSplit!!!"
    printERR $LINENO $BASH_SOURCE ${ABORT} "Check for process ownership, probably just missing permissions."
    printERR $LINENO $BASH_SOURCE ${ABORT} "On grave slow machines just a timeout may have occured."
    printERR $LINENO $BASH_SOURCE ${ABORT} "Try a following connect, if so adapt TIMEOUT value, but for this target only."
}



#FUNCBEG###############################################################
#NAME:
#  clientServerSplitSupportedVNC
#
#TYPE:
#  bash-function
#
#DESCRIPTION:
#  Checks whether the split of client and server is supported.
#  This is just a hardcoded attribute.
#
#EXAMPLE:
#
#PARAMETERS:
#
#OUTPUT:
#  RETURN:
#    0: If supported
#    1: else
#
#  VALUES:
#
#FUNCEND###############################################################
function clientServerSplitSupportedVNC () {
    printDBG $S_VNC ${D_BULK} $LINENO $BASH_SOURCE "$FUNCNAME $1"
    case $1 in
	CREATE)return 0;;
	CANCEL)return 0;;
    esac
    return 1;
}



#FUNCBEG###############################################################
#NAME:
#  enumerateMySessionsVNC
#
#TYPE:
#  bash-function
#
#DESCRIPTION:
#  Not supported.
#
#EXAMPLE:
#
#PARAMETERS:
#
#OUTPUT:
#  RETURN:
#  VALUES:
#
#FUNCEND###############################################################
function enumerateMySessionsVNC () {
    printDBG $S_VNC ${D_BULK} $LINENO $BASH_SOURCE "$FUNCNAME:\$@=${@}"
}


#
#Managed load of sub-packages gwhich are required in almost any case.
#On-demand-loads will be performed within requesting action.
#
hookPackage "${_myPKGBASE_VNC}/session"
hookPackage "${_myPKGBASE_VNC}/list"
hookPackage "${_myPKGBASE_VNC}/info"

if [ -d "${HOME}/.ctys" -a -d "${HOME}/.ctys/vnc" ];then
    #Source pre-set environment from user
    if [ -f "${HOME}/.ctys/vnc/vnc.conf" ];then
	. "${HOME}/.ctys/vnc/vnc.conf"
    fi

    #Source pre-set environment from installation 
    if [ -f "${MYCONFPATH}/vnc/vnc/cli.conf" ];then
	. "${MYCONFPATH}/conf/vnc/vnc.conf"
    fi
fi



#FUNCBEG###############################################################
#NAME:
#  handleVNC
#
#TYPE:
#  bash-function
#
#DESCRIPTION:
#
#EXAMPLE:
#
#PARAMETERS:
#  $1: <OPMODE>
#  $2: <ACTION>
#
#OUTPUT:
#  RETURN:
#
#  VALUES:
#
#FUNCEND###############################################################
function handleVNC () {
  printDBG $S_VNC ${D_BULK} $LINENO $BASH_SOURCE "${FUNCNAME}:$*"
  local OPMODE=$1;shift
  local ACTION=$1;shift

  case ${ACTION} in

      CREATE) 
	  case ${OPMODE} in
              PROLOGUE)
		  ;;
              EPILOGUE)
		  ;;
	      CHECKPARAM|ASSEMBLE|EXECUTE)
		  hookPackage "${_myPKGBASE_VNC}/create"
		  createConnectVNC ${OPMODE} ${ACTION} 
		  ;;
	  esac
          ;;

      CANCEL)
	  case ${OPMODE} in
              PROLOGUE)
		  ;;
              EPILOGUE)
		  ;;
	      CHECKPARAM|ASSEMBLE|EXECUTE)
		  hookPackage "${_myPKGBASE_VNC}/cancel"
		  cutCancelSessionVNC ${OPMODE} ${ACTION} 
		  ;;
	  esac
          ;;


      GETCLIENTPORT)
	  case ${OPMODE} in
              PROLOGUE)
		  ;;
              EPILOGUE)
		  ;;
              CHECKPARAM)
		  if [ -n "$C_MODE_ARGS" ];then
                      printDBG $S_VNC ${D_BULK} $LINENO $BASH_SOURCE "C_MODE_ARGS=$C_MODE_ARGS"
                      _C_GETCLIENTPORT=$C_MODE_ARGS
		  else
		      ABORT=1
		      printERR $LINENO $BASH_SOURCE ${ABORT} "Missing <session-label>|<session-id>"
		      gotoHell ${ABORT}
		  fi

                  ;;
	      EXECUTE)
		  printDBG $S_VNC ${D_BULK} $LINENO $BASH_SOURCE "Remote command:C_MODE_ARGS=${C_MODE_ARGS}"
		  printDBG $S_VNC ${D_BULK} $LINENO $BASH_SOURCE "CLIENTPORT(VNC,${MYHOST},${_C_GETCLIENTPORT})=`getClientTPVNC ${_C_GETCLIENTPORT}`"
  		  echo "CLIENTPORT(VNC,${MYHOST},${_C_GETCLIENTPORT})=`getClientTPVNC ${_C_GETCLIENTPORT}`"
		  gotoHell 0
		  ;;
 	      ASSEMBLE)
   		  ;;
          esac
	  ;;

      *)
          #SUSPEND|RESUME|RESET
          ABORT=1;
          printERR $LINENO $BASH_SOURCE ${ABORT} "System Error, unsupported ACTION for VNC:ACTION=${ACTION} OPMODE=${OPMODE}"
          ;;
  esac

}


#FUNCBEG###############################################################
#NAME:
#  initVNC
#
#TYPE:
#  bash-function
#
#DESCRIPTION:
#
#EXAMPLE:
#
#PARAMETERS:
#
#OUTPUT:
#  RETURN:
#
#  VALUES:
#
#FUNCEND###############################################################
function initVNC () {
  local _curInit=$1;shift
  local _initConsequences=$1
  local ret=0;


  local _raise=$((INITSTATE<_curInit));

  printDBG $S_VNC ${D_MAINT} $LINENO $BASH_SOURCE "$FUNCNAME:${INITSTATE} -> ${_curInit} - ${_raise}"

  if [ "$_raise" == "1" ];then
      #for raise of INITSTATE do not touch the OS's decisions, just expand.

      case $_curInit in
	  0);;#NOP - Done by shell
	  1)  #add own help to searchlist for options
	      MYOPTSFILES="${MYOPTSFILES} ${MYHELPPATH}/010_vnc"
              setVersionVNC $_initConsequences

              ret=$?
	      ;;
	  2);;
	  3);;
	  4);;
	  5);;
	  6);;
      esac
  else
      case $_curInit in
	  *);;
      esac

  fi

  return $ret
}