Environment Variables

SETTING/GETTING

Windows

set variable=value
echo %variable%

Variables can be configured in the System environment for all users, and/or on a per user basis via the user environment. Additional variables for jBASE can also be added to the current user configuration registry.

Win9x variables are usually configured in the AutoExec.bat. Care should be taken that the environment area does not become overwritten on Win9x as it is initially quite small, approximately 512 bytes. Subsequent .bat commands should increase the required environment space. The environment space can be explicitly increased by setting it in the config.sys file:
shell=c:\command.com /e:2048 /p

UNIX

variable=value
export variable
echo $variable

This works for all shells, although one can do "export variable=value" in ksh,etc.

Variables are usually configured in the .profile of the user login directory. Although global variables can be added to the /etc/profile script.

jBASE PROGRAMS

The jBC functions PUTENV and GETENV can be used to manipulate environment variables. For example:

IF PUTENV(envar=x) THEN ELSE NULL
IF GETENV(envar) THEN ELSE NULL

jBASE INITIALIZATION

Some environment variables can only be set before jBASE initialization. jBASE initialization occurs when the first jBASE program is executed for a particular "PORT".

The jBASE initialization process reads through the environment entries looking for possible variables required by jBASE. This process provides a substantial performance improvement as the state of these environment variables are saved for subsequent jBASE executions by either the jPML demon on Unix or the jPML files on Windows. These states continue to be valid as long as the "PORT" is still attached to a process. Some environment variables can be changed by subsequent program execution. The state of these variables are imported back into the state table after program execution.

Certain jBASE programs expect jBASE initialization to have been previously performed otherwise re-initialization will occur and resources expected by the executing program will have been removed.

For instance:

T-ATT requires a "PORT" against which it saves the tape device assignment.
SP-ASSIGN requires a "PORT" with which to save assignment status for print jobs.
READNEXT in a program after SELECT/GET-LIST.

Unix

jBASE initialization on Unix is usually performed in the .profile, via the script commands:

JBCCONNECT="jbcconnect"
export JBCCONNECT

This produces a connect string which is used to reference the port state information. If process executes an "OFF" then either "jbcconnect" needs to be re-executed via the command line or .profile on Unix or execute a jBASE program or jsh on Windows.

Windows

jBASE initialization on Windows usually occurs when the first jBASE program executes. e.g. jsh. This produces a JBCWINCONNECT variable which points to the allocated port state file.

It is important to create environment variables prior to jBASE initialization as some variables cannot be imported again after jBASE initialization.

INITIAL ENVIRONMENT VARIABLES

ADDITIONAL jBASE ENVIRONMENT VARIABLES.

EXECUTION

DEVELOPMENT

MISCELLANEOUS

TERMINAL

EMBEDDED SQL

QUERIES

CREATE-FILE

e.g. To convert all files on "jbackup" tape to J4 files set the following environment variable be using jrestore.
export JEDI_PREFILEOP=TYPE=J4 (Unix) Can use quotes to surround multiple parameters
set JEDI_PREFILEOP=TYPE=J4 (NT) Don't use quotes

JRFS

Porting