5 The VICAR Environment

5.1   VICAR Libraries
5.2   Processing Modes
    5.2.1   Interactive or Synchronous Processing Mode   VICAR DCL Mode - VMS Systems   VICAR USH Mode - UNIX Systems
    5.2.2   Asynchronous Processing   Asynchronous Processing - VMS Systems   "Background" Processing - UNIX Systems
    5.2.3   Batch Processing Mode   Batch Processing - VMS Systems   Batch Processing - UNIX Systems
5.3   VICAR Use of Subprocesses
5.4   Session Customizing Procedures
    5.4.1   Logon Procedures
    5.4.2   Logoff Procedures
5.5   Aborting a VICAR Command
Within the following section, different aspects of the VICAR environment will be covered. The user will be introduced to the VICAR Library, processing modes, and subprocesses. The user will learn how to customize a VICAR session and abort a VICAR command. The novice user should note that several concepts presented in this section are explained in more detail later on in this document.

5.1 VICAR Libraries

Seven libraries contain the executive, applications and system routines within VICAR. Each library is known by its system-wide logical name or environment variable (pointing to a system sub-directory).

     VMS         UNIX
    V2$LIB 	$V2LIB		VICAR executive routines  
    VIDS$LIB	$VIDSLIB	VICAR system routines
    TAE$UTIL 	$TAEBIN/TAEPLAT	Various system utilities
    R1LIB 	$R1LIB		Application procs
    R2LIB 	$R2LIB		Application procs
    R3LIB 	$R3LIB		Application procs
    M2LIB	$TAEMENU	Menus

Three libraries are available for application procs so that a facility may segregate its procs as it chooses.

VICAR establishes a default search hierarchy containing these seven libraries, as well as the user's current default directory. A change of the current default directory after entry into VICAR is not reflected in the search hierarchy. The user may bypass all such searches by explicitly prefixing the proc name with the library name and a colon (e.g., R2LIB:STRETCH).

The user may display the currently established search hierarchy at any time with the command show (Appendix 10.4). The default hierarchy is listed below with the search being from top to bottom.

Example: Show user's library hierarchy.

VMS: Note the location of the user's current default directory is UD:[USERID].


    User Library ($USERLIB): 

    Application Libraries ($APLIB):

    System Library ($SYSLIB):



    User Library ($USERLIB):
    Application Libraries ($APLIB): 
    System Library ($SYSLIB):
On VMS systems, liblst is a logical name which points to all the VICAR libraries.

Example: Show user's library hierarchy.


             = "VIDS$LIB"
             = "R1LIB"
             = "R2LIB"
             = "$TAEUTIL"

Within each library, compiled PDFs (file type .cpd) are given preference over slower, uncompiled PDFs (file type .pdf). Therefore, a program which has a .cpd and a .pdf will always have its faster version chosen. See Section 7.3.6 for more information on compiled PDFs.

This default hierarchy is easily altered either with the use of the intrinsic command setlib (Appendix 10.4), or within the user's ULOGON procedure (Section 5.4.1).

Example: Place starlib: in front of the current library list and display.

    VICAR>setlib (starlib:,*)

    User Library ($USERLIB):

    Application Libraries ($APLIB):

    System Library ($SYSLIB):
Example: Delete starlib: from the current library list and display.

    VICAR>setlib-delete starlib:

    User Library ($USERLIB):

    Application Libraries ($APLIB):

    System Library ($SYSLIB):

5.2 Processing Modes

The user has several types of processing modes available within VICAR. Each mode is described in detail within this section.

5.2.1 Interactive or Synchronous Processing Mode

When a user communicates directly with VICAR by means of a terminal, and VICAR immediately acknowledges and executes the user's requests, the user is in the "interactive processing mode". Within the interactive session the user might use: VICAR DCL Mode - VMS Systems

On VMS systems, the user has the ability to execute DCL commands without leaving the VICAR environment. The user can execute a single DCL command, or actually enter the DCL mode while still within VICAR.

In the first case, the user is able to execute a one line DCL command by typing DCL and the command.

Example: Execute a DCL command from VICAR.

If the user wanted to do something in DCL that requires more than a single command line, a second method is available. If, for example, the user wanted to send a mail message or edit a file, DCL would be typed at the VICAR prompt. The user would then receive a new prompt, _$, indicating that the DCL mode of VICAR had been entered.

Syntax: Enter VICAR's DCL mode.


Within this mode the user is able to do almost everything that could be done in the normal DCL mode. Some DCL programs may not work in VICAR's DCL mode.

The normal VICAR mode can be re-entered by typing EXIT, VICAR or Control-Z.

Syntax: Return to VICAR from DCL mode.

    _$ EXIT
    VICAR> VICAR USH Mode - UNIX Systems

Similarly, on UNIX systems, the user has the ability to execute UNIX shell commands without leaving the VICAR environment by typing ush at the command line. (USH stands for User SHell.) However, ush should be used much less frequently than dcl is, because in a windowing environment it makes more sense to open another window than to suspend VICAR in order to execute shell commands. The ush command should be used primarily in procs rather than interactively.

Example: Execute a USH command from VICAR.

    VICAR>ush df
Syntax: Enter VICAR's USH mode.

The 'shell' that is invoked is the command interpreter 'sh' or 'csh' as defined by the symbol SHELL when you logged in. You may redefine the value of SHELL from 'sh' to 'csh' or vice versa before invoking TAE.

The normal VICAR mode can be re-entered by typing Control-D, or exit at the shell prompt.

Syntax: Return to VICAR from USH mode.

    % exit

BEWARE Changing the default device/directory via the shell command cd while in USH mode or terminating a USH command with a backslash (\) will cause TAE to malfunction.

5.2.2 Asynchronous Processing

EXPERT The Asynchronous processing mode allows a user to execute a proc in a separate subprocess without interfering with the user's current interactive session. This mode may sometimes be preferable to the Batch mode because the separate subprocess runs simultaneously with, and at the same priority as, the interactive session. The user's interactive environment is duplicated in the asynchronous subprocess, thus relieving the user from having to redefine commands and globals. More than one asynchronous job may run at the same time. Once submitted, the job is executed immediately.

EXPERT Because asynchronous jobs are executing in a separate subprocess, they cannot directly communicate with the user's terminal. However, they may communicate indirectly by requesting additional parameter inputs. See the TAE Command Language User's Manual and Section 7.2.5 for further information on these "dynamic parameters". Asynchronous Processing - VMS Systems

EXPERT For asynchronous jobs run on a VMS system, the VICAR runstream information is written into a log file named PROCNAME.TML.

Example: Submit TESTGEN.PDF as an asynchronous job.

    [TAE-ASYNCJOB]Asynchronous job 'TESTGEN' initiated.

The user may check on the status of the job with the intrinsic command SHOW-ASYNC.

Example: Monitor the progress of TESTGEN




BEWARE The user should not exit a VICAR interactive session while asynchronous jobs are executing. If this happens, all asynchronous jobs will be aborted.

BEWARE The user is also advised to avoid using tape operations within the Asynchronous mode until a known bug can be corrected. Tape drives can be successfully allocated, mounted, written or read. However, the tapes cannot be successfully dismounted and/or remounted within the Asynchronous mode. "Background" Processing - UNIX Systems

VICAR running on UNIX systems does not have an "asynchronous mode"; given that a user can have several windows open at the same time, it is usually unnecessary. However, processing jobs in the "background" is similar in concept.

To do this, your proc will need to be submitted from the shell prompt.

Example: Submitting a VICAR proc from the shell prompt. (Note: this only works on SunOS, not Sun Solaris systems.)

    % cat test.pdf
    Procedure	!test
    gen out.img 10 10
    label-list out.img
    ush ps
    % taetm test > test.log &
    [1] 9147
The slogon statement in the proc after the Body command is necessary if the proc is going to be run from the UNIX shell prompt. However, it may not be present when running the proc from the VICAR command line. The > sign redirects the output from the proc to the file test.log, rather than to your screen. (There is currently a bug in VICAR, such that the output is not written to the output file in the correct order. This should be fixed in future versions.) The ampersand (&) forces the job into the background. Typing fg at the prompt will bring the job back into the foreground.

5.2.3 Batch Processing Mode

The user may wish to execute a proc in batch. Batch processing is achieved by means of submitting a file, commonly referred to as a job, to a batch queue which will create the proper environment to execute a proc. Upon submitting the file, the user relinquishes control of the job to the operating system, thus freeing the terminal and allowing the user to continue with other tasks. The user may check on the status of the job with the intrinsic command SHOW.

BEWARE The default directory for a batch job is the directory from which the submittal occurred. If submitted from a subdirectory, all file names should be fully qualified because this subdirectory may not exist on all disks referred to in the job. Batch Processing - VMS Systems

EXPERT There are several ways to invoke batch processing in VICAR on VMS systems. This section will address the VAX/VMS default batch queue, SYS$BATCH. If this queue is not on the user's system, consult the local system manager for information on what is available.

EXPERT One way to create a batch process is to use the intrinsic command BATCH-SUBMIT (Appendix 10.4). After Tutoring on a desired proc and performing a Tutor SAVE (Appendix 10.8) on the parameter values selected, the user can submit a job with the BATCH-SUBMIT command. This can be done in a Tutor session on BATCH-SUBMIT or interactively.


    VICAR>+ SAVEFILE=savefile_name QUEUE=queue_name +
    VICAR>+ STDOUT=output_file
Example: After specifying parameters in Tutor on proc GEN, submit to batch queue.
    Job 2038 submitted to queue SYS$BATCH
    Job GEN (queue SYS$BATCH, entry 2038) completed

EXPERT Another method for submittim a job is to use the command qualifier RUNTYPE (Section Specifying a valid queue_name or NORUN will produce two different submitting techniques. Specifying SYS$BATCH as the queue_name causes the job to be automatically placed in that queue and executed.

Example: Submit proc TESTGEN to batch queue SYS$BATCH

    Job 2039 submitted to queue SYS$BATCH

    Batch queue MIPL1_SYS$BATCH, on MIPL1::

	Jobname	    Username	Entry	Status

	TESTGEN	     USERID	2039	Executing
    Job TESTGEN (queue SYS$BATCH, entry 2039) completed
EXPERT Specifying NORUN as the queue name disables the act of job submittal. Instead, a job file is created containing all commands needed to execute the proc in batch. This method allows the user to issue the DCL SUBMIT command with any or all of its associated qualifiers, rather than accepting the VICAR defaults.

Example: Create the job file for TESTGEN proc before submitting it.

    Created batch job file 'TESTGEN.JOB'.
EXPERT The .JOB file (TESTGEN.JOB for this example) would then be submitted using the DCL SUBMIT command, unless other provisions have been made by the system manager.

Example: Submit TESTGEN.JOB to SYS$BATCH queue.

  Job TESTGEN (queue SYS$BATCH, entry 2041) started on SYS$BATCH
  Job TESTGEN (queue SYS$BATCH, entry 2041) completed
EXPERT Upon completion of a batch job, the user can access a file containing all of the processing information collected during the batch job execution. The log file is located in the directory from which the job was submitted, and it is called PROCNAME.LOG (TESTGEN.LOG for the above example).

EXPERT The user may also delete a batch job at any time.


    VICAR>BATCH-DELETE QUEUE=queue_name JOBID=xxx Batch Processing - UNIX Systems

Formal batch processing does not exist on UNIX systems at the current time. However, it is possible to submit a job to run at a later time, perhaps when the system load will be lower. This may be done by creating a shell script to initiate your proc. This shell script is submitted as a "batch" job by using the UNIX at command. (The UNIX cron command could also be used.)

Example: Use of the at command on a SunOS system. (Batch processing doesn't work on Solaris systems currently, but when it does, be aware that the at command has a slightly different syntax on those systems.)

    % cat submit_test.sh
    taetm test
    % at 23:00 submit_test.sh
    job 11719 at Tue Aug  9 23:00:00 1994
(Remember to turn the execution permission for your shell script on using the UNIX command chmod u+x submit_test.sh). You will receive a mail message containing the output from your job when it is completed. As stated above in Section, there is currently a bug in the output files from these batch jobs.

5.3 VICAR Use of Subprocesses

This section is relevant for VMS systems only.

WIZARD The VICAR executive makes use of VMS subprocesses to establish environments and isolate functions. This discussion is intended to clarify how a user's session is being supported under the VMS operating system.

WIZARD A user logged in under VMS has a process associated with the session, e.g., process name PRCNM. Entering the command VICAR starts a VMS subprocess with a process name PRCNM1. This subprocess is the environment under which all VICAR operations are handled. The VICAR EXIT command returns the user to the parent VMS process and deletes the subprocess and all its descendent subprocesses.

WIZARD In the case of a batch job submittal (Section 5.2.3) from VICAR, a separate VMS process is initiated. The name of the submitted procedure PDF is taken as the process name of the batch job, e.g., MYPDF. When the job begins to execute, a subprocess (MYPDF1) is created as the environment from which the VICAR commands are executed. Both process and subprocess, of course, go away at job termination.

WIZARD Asynchronous processes (Section 5.2.2) are handled similarly. They differ from batch jobs in that a subprocess is initiated under which a second subprocess is created for the VICAR environment. The process name of the first subprocess is created by concatenating the eight character Process ID number of the VMS process with the first four characters of the PDF being run and appending a character zero. Therefore, the first subprocess may have a process name like 22058225IMAG0. The second subprocess gets that name with a "1" appended to it.

WIZARD The following diagram illustrates the relationships of the VMS processes and subprocesses utilized by VICAR.

WIZARD Because of this interesting relationship of processes and subprocesses, a user must realize that observing the progress of a process with a DCL SHOW SYSTEM command, for instance, may be meaningless because most of the action is occurring within one or more subprocesses.

WIZARD Normally, actions performed in DCL mode of VICAR will take place in the subprocess. It is possible, however, to affect the parent process as well (see Section for more discussion in this area). DCL commands which allow the /JOB qualifier affect both the parent and the subprocess when the qualifier is present.

Example: Define and use a logical name for a parent and subprocess.


5.4 Session-customizing

Logon and logoff procedures are used by VICAR to create the proper environment. VICAR invokes its own logon and logoff system procedures upon entering and exiting the system. The session may be further customized by the execution of the user's logon and logoff procedures. The creation of the user procedures are explained in the following sections. The examples presented are very useful and might be used as a starting point.

5.4.1 Logon Procedures

When the user enters VICAR, the system logon procedure, slogon, is invoked. slogon is a facility-dependent logon procedure which is normally invisible to the interactive user and is typically created and maintained by the system manager. Once VICAR has been invoked, the operating system executes this logon procedure and a series of steps are executed in order to set up the VICAR environment. One of the last steps in the startup procedure is to examine the user's present directory for a ulogon.pdf and to execute that procedure if it exists.

The ulogon is a procedure typically written and maintained by the user in order to customize the initialization of the VICAR. The ulogon is not a required procedure but most users find it very useful. For example, the ulogon can be used to define the user's VICAR commands, specify the location of the directories where the user's application software resides or to configure the user's VICAR session.

Example: ulogon.pdf (A detailed, line-by-line, description can be found in Appendix 10.11).

    Refgbl $PROMPT
    Refgbl $BECHO
    Refgbl $ECHO
    DEFCMD SCR "Enable-script"
    DEFCMD CHK "Syntax check"
    DEFCMD NOCHK "Syntax nocheck"
    DEFCMD QUE "ush lpq"
    LET $ECHO= "YES"
    LET $BECHO= ("YES","YES")
    LET $PROMPT="GoGetum"
The user may define a VMS logical name to point to a ulogon. Doing this causes the same ulogon to be executed regardless of the default directory. At the current time, this cannot be done on UNIX systems, and a user must have a copy of their ulogon.pdf in each directory from which they wish to run VICAR.

Example: Define a VMS logical name, in user's LOGIN.COM, pointing to user's ULOGON.

Alternatively, the user could have a custom ulogon in each directory by not defining the logical name and maintaining separate ulogons.

5.4.2 Logoff Procedures

The slogoff is a facility-dependent logoff procedure which is activated when the user exits from VICAR. One of the steps in the procedure is to examine the user's current directory for a ulogoff.pdf and to execute that procedure if it exists.

The ulogoff is typically written and maintained by the user in order to customize the exiting from the VICAR session. The ulogoff is not a required procedure but some users find it to be very useful for directory maintenance. For example, the ulogoff can be used to delete unnecessary files from the user's directories or to automatically print out the latest version of the session.log.

Example: ulogoff.pdf (A detailed, line-by-line, description can be found in Appendix 10.11)

    ush /bin/rm last.par
    ush /bin/rm session.tsl
    ush lpr session.log
As with the ulogon the user should define a VMS logical name to point to a ulogoff. Doing this causes the same ulogoff to be executed regardless of the default directory. (Again, this is not currently possible on UNIX systems.)

Example: Define a VMS logical name, in user's LOGIN.COM, pointing to user's ulogoff.

Alternatively, the user could have a custom ulogoff in each directory by not defining the logical name and maintaining separate ulogoffs.

5.5 Aborting a VICAR Command

VICAR provides the user with the ability to interrupt a VICAR operation once execution has started. VICAR has defined the key sequence Control-C to activate "proc interrupt mode". Upon entering Control-C, the operation is suspended and the user is prompted by the "interrupt prompt" for appropriate commands.


The user may enter one of the following commands:

Note: If a synchronous proc is invoked, the following error is issued:

    [TAE-NOSYNC] Synchronous procs not available in proc 
interrupt mode.
While a proc is interrupted, it is valuable to be able to perform Intrinsic commands and then resume the proc. The commands will take effect immediately.

Example: Specify an Intrinsic command and resume a proc.

    VICAR-INTERRUPT>let $echo="yes"
BEWARE Control-C is the only sequence defined for "Proc interrupt mode". Other control characters will have very different results. (See Section for more information.)

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