Overview of a FOCUS Session

The focus command invokes a shell script, which performs the following functions and then starts the binary program:

1. Assigns default values to UNIX variables that create the desired environment for the executable code. For information on what these variables control and how to assign a value other than the default, see Defining the FOCUS Operating Environment.
2. Checks whether the user has write access for the current directory. If the user does not have appropriate access, the script issues an error message and does not start FOCUS.

To begin a FOCUS session, issue the following command at the UNIX prompt:

focus

This command invokes the focus shell script. You can specify optional parameters that determine FOCUS behavior immediately following the focus command. For a list of options, see Defining the Environment Using Command-Line Parameters.

FOCUS displays one of the following.

• The FOCUS prompt (>>). To use FOCUS, issue the desired commands at the prompt. To end the session, issue the following command at the prompt:

  FIN

• A site-specific application. To use the application or end the session, follow the directions provided by the application.

FOCUS supports the following levels of profiles to provide flexibility in designing and running applications.

• A global profile is a startup file that is automatically created during the FOCUS installation and configuration. It contains the default environment settings that are required for the proper FOCUS operation.
• A group profile is a file used by FOCUS to specify settings that apply to a FOCUS environment, but only for a user of a specific security group.
• A user profile is available, based on a user ID. A user profile is a file used by FOCUS to specify settings that apply to a FOCUS environment, but only for a specific user ID.

When you start FOCUS, it searches in the current directory for a FOCUS procedure called profile.fex. If this file exists, FOCUS executes it. If there is no profile.fex in the current directory, FOCUS searches the directories specified in the FOCUS search path for profile$.fex, executing the first one it finds. If FOCUS finds neither of these profiles, it displays the prompt and awaits further instructions.

To stop a running program during a FOCUS session, press the UNIX Interrupt key, which sends an operating system signal to interrupt the session and close the files. On most systems, the Interrupt key is either Ctrl+C or Delete. If you do not know which key to use, issue the following UNIX command:

stty -a

The attribute intr identifies the Interrupt key.