When the host system on which you run your Natural applications is a UNIX system, additional software for the Natural UNIX protocol has to be installed on the host. The Natural UNIX protocol modules are shipped together with Natural for UNIX.
The protocol enables:
The option to change the host password via the Natural Screen Tester Base Object.
Support for a non standard screen size.
User permissions are now received directly from the host. Note that currently it is not possible to log in to the host without providing a user name and password unless you use a customized User Exit authentication function.
Host keys are automatically recognized by Natural Screen Tester and do not need to be identified according to their pattern.
It is now possible to define the authentication method and authentication localization texts.
The configuration has been improved. It is possible to specify the Natural parameter file in Natural Screen Tester Designer, using the same port for a number of applications in parallel, without making changes in the host.
The following topics are covered below:
Supported Operating Systems
The same platforms as those supported by Natural for UNIX.
Other Software Products
Natural Version 6.3.2 or above for UNIX.
Linker
A linker (for example, lD or cc) and the command make must be available in the system.
Setting up APX on UNIX consists of the following steps
Note:
This step is only required for an upgrade installation. It is not
required when you install Natural for UNIX for the first time.
Stop the apxsrvd
process using one of the following commands: apxsrvd.sh servicename
stop
or
apxsrvd.sh portnumber stop
Repeat this command for each service that has been started.
Ensure that the environment definitions, as described in setup.txt in the root directory of the Natural CD, are correct and set.
Note:
Special note for Red Hat Enterprise Linux AS: On Red Hat
Enterprise Linux AS, only PAM authentication, working with local-machine users
is supported (for example it is not possible to use PAM with WinBind for active
directory authentication. Implement UserExit1 to use PAM this way). Therefore you
have to create a file /etc/pam.d/apxsrv containing the
following two lines:
#%PAM-1.0 auth required
/lib/security/pam_unix.so nullok
Natural Screen Tester Natural UNIX protocol is installed during the Natural installation.
Important:
The Natural installation provides a APX option which must be
activated. For more details, see your Natural installation documentation.
When you install Natural with APX, the directory $NATDIR/$APXNODE is created. The template files located in $NATDIR/$NATVERS/apx/node-name are then copied to this new directory. The APX daemon $NATDIR/$NATVERS/apx/bin/apxsrvd requires a TCL shared library which is delivered in the $NATDIR/$NATVERS/lib directory. It is linked to the runpath /opt/softwareag/nat/$NATVERS/lib (for Natural Version 6.3) or /opt/softwareag/Natural/v<version>/lib (as of Natural Version 8.3), and is installed with permissions 6755 (s-bit). As the s-bit is used, $LD_LIBRARY_PATH is not searched. Therefore, ensure that the apxsrvd daemon can locate the TCL shared library. This can be done by installing Natural in /opt/softwareag and setting a symbolic link from /opt/softwareag to your current $SAG directory, or making the TCL shared library available from a system directory.
The APX-specific settings are shown below:
| Environment Variable | Description |
| Natural Screen Tester_ROOT | Home directory. |
| APXNODE | Name of the node on which APX is installed. |
| APXSERV | Name of the path to the apxservice file. |
| APXTIMEOUT | Number of seconds that the daemon waits for an input from the Natural Screen Tester server side (SO_TIMEOUT). |
The following directories are created when Natural is installed together with Natural Screen Tester on a UNIX system:
| Directory | Description |
|---|---|
| $NATDIR | Top-level Natural directory. |
| $NATDIR/$NATVERS | Directory with all components for the current Natural version. |
| $NATDIR/$NATVERS/apx | Directory with the APX components. |
| $NATDIR/$NATVERS/INSTALL | Shell scripts and environment files to required to install the product. |
| $NATDIR/$NATVERS/apx/bin | APX executable files. |
| $NATDIR/$NATVERS/apx/node-name | Contains the template files (services.dat, apxservice, etc.). |
| $NATDIR/$NATVERS/apx/samples/userexit | Contains the files for building the sample user exit. |
| $NATDIR/$NATVERS/bin/build | Contains the library (libapx.a) to link with Natural. |
| $NATDIR/$NATVERS/bin/build.tr | Contains the trace library (libapx.a) to link a trace version with Natural. |
| $NATDIR/$APXNODE | Contains the configuration files (services.dat, apxservice, etc.). |
Note:
The above table lists only the most important directories and
files.
When the APX installation finishes, the directory $NATDIR/$APXNODE will contain the following configuration files:
| Configuration File | Description |
|---|---|
| apx.sh | Shell script to start the Natural application. |
| apxsrvd.sh | Shell script to start and to stop the daemon. |
| apxsrvd.conf | Contains the parameters required to configure the authentication method and the localization text. |
| Apxenv | Default environment script file for bash. |
| apxenv.csh | Default environment script file for cshell. |
Any Natural application can be used with Natural Screen Tester.
To start a new Natural application, proceed as follows
Create a new parameter file using the Natural Configuration Utility (see
the Natural documentation) and modify the STACK command as follows: logon
library; startprogram; fin
Locate a service/port number which is not in use.
When necessary configure the apx.sh shell script. This script is called from the APX daemon in order to start a Natural session. It has the following content:
#!/bin/sh # Extract the arguments IP_ADDR=$1 CLIENT_ID=$2 PARAMETERS=$3 CUSTOM=$4 # Trace #PT_TRACELEV=i6000 #SAGTMP=$HOME/tmp #export PT_TRACELEV #export SAGTMP # Natural Data Transfer NSWUCI_FD=$UNIUCI_FD export NSWUCI_FD # $NATDIR/$NATVERS/bin/natapx parm=$PARAMETERS etid=$$ >/dev/null 2>&1
The shell script will receive the following arguments:
- IP_ADDR
The client IP address from where the session is opened.
Note:
If there is a proxy, this will not be the IP address of the Natural Screen Tester server workstation. Instead, it will be the IP address of the proxy.- CLIENT_ID
When connecting with the Natural Screen Tester server, the value of this argument will always be Natural Screen Tester.
- PARAMETERS
The Natural parameters file as it appears in Natural, without the file extension. This file is passed to the parm argument in the Natural command line. The value of the PARAMETERS argument is taken from the Natural Screen Tester server configuration (as defined in the Natural Screen Tester Designer, in the Host Configuration dialog box).
- CUSTOM
For future use.
When necessary configure the apxsrvd.conf file:
The configuration file apxsrvd.conf contains information that the user exits need for the APX daemon. It includes the following content:
[UserExits] ; UserExit1=/FS/sag/nat/apxexuex/userexit1/libapxuserexit1.so [PasswdArguments] Parameters= [PasswdMessages] EnterOldPassword=Enter existing login password: NewPassword=New Password: ReEnterNewPassword=Re-enter new Password: PasswordSuccessful=passwd: password successfully changed for*
- [UserExits]
The following user exit can be defined:
- UserExit1
The library that is defined by UserExit1 contains the following function:
int apx_CheckUsernameAndPassword(const char *pUsername, const char *pPassword, const char *pNewPassword, char *pErrorMessage)If the key UserExit1 is defined in the configuration file, the function
apx_CheckUsernameAndPasswordis responsible for checking the user name and password. If a new password is received, user exit 1 is also responsible for changing the password.When there is an error, the return code of the function must be "0"; in this case, the
pErrorMessageis returned to the client. When the user name and password are correct, the return code must be a value other than "0".- [PasswdArguments]
The key Parameter is used to define any additional parameter(s) that have to be passed to the
passwdcommand. For example:
passwd -r ldap- [PasswdMessages]
The keys in this section define the messages that are to be returned by the system (passwd command) when a user changes the password. If any of these messages are not identified by the daemon, an error will be returned to the client.
- Password Mechanism
The password and new password are encrypted on the client side and decrypted on the UNIX side. A maximum of 8 characters is allowed.
When user exit 1 is active, the user name, password and new password parameters are passed to the user exit. When user exit 1 is not active, the daemon checks whether the user name and password are correct for the system. If a new password is sent, the daemon changes the password by calling the UNIX command passwd.
The APX daemon is responsible for accepting new sessions. This daemon can be started and stopped using one of the following commands:
apxsrvd.sh servicename [start|stop]
apxsrvd.sh portnumber [start|stop]
Note:
The daemon must be started on a service/port which is not yet in
use.
To troubleshoot problems in the APX component's functionality it is possible to define tracing its activity. The daemon and the Natural application with the APX lib can be traced separately. In order to determine which of the two components' activity should be traced follow these guidelines: when the problem seems to be to do with connecting the Natural Screen Tester Server to the APX daemon (including authentication problems), trace the daemon component. For any other problems trace the Natural application. Note that it is not recommended to use the trace file in the production environment on a regular basis.
To trace the APX daemon
Go to the $NATDIR/$APXNODE directory.
Edit the apxsrvd.sh file.
Find EXECUTABLE=apxsrvd, and change it to EXECUTABLE=apxsrvd.tr
Define the following environment variables (the following is an example of how these should be defined in sh/bash):
> PT_TRACELEV=i6000 > SAGTMP=$HOME/tmp > export PT_TRACELEV > export SAGTMP
The trace files are created in the $SAGTMP directory. In the example above this is $HOME/tmp.
Restart the daemon:
> apxsrvd.sh servicename stop > apxsrvd.sh servicename start
or
> apxsrvd.sh portnumber stop > apxsrvd.sh portnumber start
To trace the Natural Application with the APX library
Go to the $NATDIR/$APXNODE directory.
Edit the apx.sh file.
$NATDIR/$NATVERS/bin/natapx parm=$PARAMETERS etid=$$
>/dev/null 2>&1
Change natapx to natapx.tr
Uncomment (by removing the # from the beginning of the rows) the TRACE section.
The trace files are created in the $SAGTMP directory.
By default it is $HOME/tmp. It will take effect when next connecting to the daemon.
If the host system on which you run your Natural applications is an OpenVMS system, additional software for Natural Screen Tester has to be installed on the host. The Natural Screen Tester OpenVMS modules are shipped on the Natural OpenVMS CD. In general, Natural Screen Tester uses the default system parameter values provided with the OpenVMS system.
Supported Operating Systems: The same platforms as those supported by Natural for OpenVMS.
Other Software Products: Natural for OpenVMS 6.3.8 or above.
Setting up Natural Screen Tester on OpenVMS consists of the following steps:
Stop the Natural Screen Tester Daemons: This step is only required for an upgrade installation. It is not required when you install Natural Screen Tester for the first time.
Stop the apxsrvd process using the following command:
stop servicename
Repeat this command for each Natural Screen Tester service that has been started.
Establish the Environment: Ensure that the environment definitions, as described in readme.txt in the root directory of the Natural CD, are correct and set.
Install Natural and Natural Screen Tester: Natural Screen Tester is automatically installed during the Natural installation. When you install Natural and Natural Screen Tester, the directory NATDIR:[apxnode] is created, where apxnode contains the system name. The template files located in NATDIR:[natvers.APX] are then copied to this new directory.
Check the Environment for Natural Screen Tester: Besides the logical names NATDIR and natvers as defined by Natural, Natural Screen Tester needs the following logical names which are created during the installation of Natural:
| Logical Name | Description |
|---|---|
| apxnode | Contains the system name. |
| VAXC$PATH | Contains the physical device specification of NATDIR:[natvers.BIN] |
Example:
Define VAXC$PATH="ALF9$DKB500:[NATURAL.V41212.BIN]"
In addition, the logical names NATOW and NATFE are redefined during the start of the daemon process to point to the Natural Screen Tester images NATAPXnatvers.EXE and NATFEAPXnatvers.EXE.
Optional. If function keys and message lines are to be displayed in their native format (i.e. as normal text), set the environment variable APX_PF_MSG_LINES_NATIVE_FORMAT to "YES":
Define APX_PF_MSG_LINES_NATIVE_FORMAT="YES"
If APX_PF_MSG_LINES_NATIVE_FORMAT is not set or if its value is not "YES", function keys and message lines are detected automatically (default). If they are to be treated in a special way, you have to define the basic rules Function Keys and Message Line in the same way as for a mainframe screen.
Check the OpenVMS UAF Parameters: Check the OpenVMS UAF (user authorization file) parameters listed in the table below and, if necessary, modify them. The size values of these parameters for the APXSRVD daemon are important. The sizes depend on the number of sessions that are started by the daemon. Natural error messages will occur if the size limits are reached or if no more quotas are available. In these cases, you have to increase the values so that they meet your needs.
| Parameter | Recommended Value |
|---|---|
| Fillm | Approximately 50 for each session with Natural Screen Tester. |
| Prclm | 50 |
| Bytlm | Approximately 30000 for each session with Natural Screen Tester. |
| BIOlm | 10000 |
Define the TCP Port Number: The UCX service with the TCP port number must be defined in the system as follows:
$ UCX SET SERVICE APXDEMO /PORT=22370 /FILE="" /USER="" /PROC=""
Instead of APXDEMO and the above port number, you can also specify other values. For example, you can create or define the TCP service name APXAPPL1 with the port number 25000.
The following directories are created when Natural is installed together with Natural Screen Tester on an OpenVMS system:
| Directory | Description |
|---|---|
| NATDIR | Top-level Natural directory. |
| NATDIR:[natvers] | Directory with all components for the current Natural version. |
| NATDIR:[natvers.INSTALL] | Shell scripts and environment files to install the Natural product. |
| NATDIR:[natvers.BIN] | Natural Screen Tester executable files NATFEAPXnatvers.EXE, NATAPXnatvers.EXE and APXSRVDnatvers.EXE. |
| NATDIR:[natvers.FNAT] | Contains the old Natural demo application SYSEXAPX for Natural Screen Tester. |
| NATDIR:[apxnode] | Contains the configuration files APXSRVD_servicename.COM, APXSRVD_servicename.LOG, SERVICES.DAT and START_APXSRVD.COM. |
The files APXSRVD_servicename.COM and APXSRVD_servicename.LOG are created when the Natural Screen Tester daemon APXSRVDnatvers.EXE is started with the procedure START_APXSRVD.COM.
servicename is the UCX service as defined in the file SERVICES.DAT.
natvers indicates the version number and patch level of the corresponding Natural version.
The configuration file SERVICES.DAT is located in the directory NATDIR:[apxnode], where the apxnode contains the node name (for example, NATDIR:[ALF9]SERVICES.DAT).
The content of this configuration file is one line for each defined TCP service:
servicename username natural parm1 ... parmn
| servicename | Must be the same name as used in the TCP port number definition (see above). |
| username | Not used. |
| natural | This is the program name which must not be changed. |
| parm1 … parmn | Dynamic Natural parameters. |
Example:
apxdemo sag natural parm=mypar bp=bp1 apxapp1 sag natural parm=app1 bp=bp1 apxapp2 sag natural parm=app2 bp=bp2
Note:
If the APXSRVDnatvers daemon does not detect Natural's dynamic
parameter ETID, the daemon automatically adds the ETID to the list of the
dynamic parameters to be passed to Natural. The ETID added by the daemon has
the format ETID=number_ username. It is truncated if the string exceeds 8
characters.
The BYPASS privilege must be authorized for the account to start the Natural Screen Tester daemon. The BYPASS privilege must also be set for the daemon process.
When TCP port number and service have been defined (UCX) and the SERVICES.DAT template file has been modified according to your requirements, you can start the APXSRVD daemon to use Natural Screen Tester.
To start the daemon, invoke the DCL procedure START_APXSRVD.COM as follows:
@START_APXSRVD.COM service natvers
service contains the name of the service as defined with UCX.
natvers defines the Natural version and patch level.
If both parameters service and natvers are omitted, the defaults APXDEMO and the current Natural version are used. The command procedure creates the temporary file APXSRVD_ servicename.COM which sets up the environment and creates all logicals for Natural Screen Tester and starts the daemon.
Once the daemon has been started, the file APXSRVD_ servicename.LOG is created. This file contains information (including the errors) about the daemon.
APXSRVD_ servicename.COM and APXSRVD_servicename.LOG are located in the directory NATDIR:[apxnode].
Note:
The account which starts the daemon must hold the privilege
IMPERSONATE as the default privilege. It is not sufficient to have an
authorized privilege.
There are error situations in Natural Screen Tester which force the termination of the Natural session. For example, when the user chooses the close button in the upper right corner of the Natural Screen Tester window, the communication with the Natural application is disconnected immediately. Then also the Natural process finishes execution immediately without running through the normal close down code of the application. This may lead to inconsistencies in the system, for example, if the corresponding entry for the Natural process remains in the database user queue.
Natural Screen Tester returns error codes to Natural which can be used in a Natural error handling routine. To make sure that the close down code of your application is always executed, write an error handling routine which identifies the Natural Screen Tester fatal errors or add this code to your existing error handling routine. For critical errors, move the command FIN to the top of the Natural stack in order to finish and close everything correctly.
The Natural Screen Tester critical errors are:
| 6296 | Fatal error in the communication. The communication will be disconnected immediately. |
| 6297 | Fatal error allocating memory. |
This Natural program reads the employees file stored in Adabas. The program moves ERRGEN to *ERROR-TA to check any Natural error.
DEFINE DATA LOCAL 1 VIS VIEW OF EMP 2 AA-1 END-DEFINE MOVE "ERRGEN" TO *ERROR-TA READ VIS DISPLAY AA-1 END-READ END
This Natural program with the name ERRGEN checks the Natural error number. If the error number is 6296 (fatal error in the communication), the program stacks the command FIN on top of the Natural stack. The Natural execution finishes immediately and all databases are closed.
DEFINE DATA LOCAL 1 ERRNUMBER (N4) 1 LINENUMBER (N4) 1 STATUS (A1) 1 LEVEL (A2) 1 GNPGACTU (A8) END-DEFINE INPUT (SG=OFF) ERRNUMBER LINENUMBER STATUS GNPGACTU LEVEL IF ERRNUMBER=6296 STACK TOP COMMAND "FIN" END-IF END
There are several restrictions when using the presentation clients with Natural applications on UNIX hosts:
Runtime errors in Natural UNIX applications are handled by the default NSWUCIET error transaction. The user can define another error transaction by setting the *ERROR-TA Natural system variable. See the Natural documentation for details. Sample Natural error transaction:
DEFINE DATA LOCAL 1 ERR_INFO 2 ERR_NR(N5) 2 ERR_LINE(N4) 2 ERR_STAT(A1) 2 ERR_PNAM(A8) 2 ERR_LEVEL(N2) END-DEFINE INPUT ERR_INFO DISPLAY ERR_INFO STACK TOP COMMAND 'E' END
Starting with Natural 6.1, a default error transaction named NSWUCIET will be used if Natural is running with Natural Screen Tester and an error transaction has not been set by the user.
You cannot use Natural applications that return to the Natural main screen. This always leads to wrong screen display and a loss of the session.
You cannot use the Natural utilities such as SYSMAIN, SYSDDM and editors such as NATEDIT. This always leads to wrong screen display and a loss of the session.
You cannot use any Natural system command such as CATALL, FIND, GLOBALS, HELP, KEY, LIST, SCAN or XREF. This always leads to wrong screen display and a loss of the session.
You should not use the Natural commands SETUP and RETURN as this may lead to a loss of the session. • Terminal commands Terminal (%) commands are not supported. They do not work when entered in a presentation client.
The error messages of an internal REINPUT are not displayed in the presentation clients (for example, if you enter the number 500 into a I1 field: NAT1142). Examples of such messages:
| NAT1142 | Input results in integer value overflow. |
| NAT1125 | Too many significant digits in numeric input value. |
| NAT1143 | Input does not correspond to input edit mask. |
| NAT1011 | Requested function key not allocated. |
When using the presentation clients with Natural applications on UNIX hosts, the Natural system variable *INIT-ID will not be filled with a value for the terminal type. Instead, it will contain the value notty.