Task environment

Task environment functions are used to manage task environment variables.

All task environment functions and procedures act on the EPM environment variables env and runenv.

env and runenv are list variables that contain all of the environment variables that are defined for the current request. env is a read-only variable that contains task information from the initial task request on the submit host. runenv is a modifiable variable that contains the task information that is actually used during task execution on the run host.

env and runenv have the following format:

{"variable-name=value", "variable-name=value", …};

getenv

Description

The getenv() function returns the value of the environment variable that is specified in the name parameter.

Values that are returned by getenv are unaffected by the setenv, keepenv, and unsetenv procedures, because getenv accesses the user’s original, read-only task environment variable information that is stored in the env variable from the client on the submit host.

Syntax

result = getenv (name, value);

Arguments


name	Required. A string that contains the name of a task environment variable.
value	Optional. A string that contains the value to use if the environment variable name does not exist in env.

Return values

If the specified task environment variable is found, then result contains its value.

If the specified task environment variable is not found, then the value returns as a string. If value is not specified, then an empty string is returned.

Example

In this example, the value of the environment variable TZ is retrieved from env and stored in result. If TZ is not found, then result is empty.

result = getenv ("TZ");

keepenv

Description

The runenv variable is a list in which each element contains an environment variable. The format of a runenv element is name=value, where name is the name of an environment variable and value is the current value of that variable.

The keepenv procedure modifies the runenv variable so that it contains only the variables that are listed as input parameters. All other environment variables that are stored in the runenv variable are deleted.

keepenv is typically used to limit the set of environment variables that are available to the current task during execution.

Syntax

keepenv (name1, [,name2, …]);

Arguments


name1	Required. String that contains the name of a task environment variable that should be stored in runenv.
name2	Optional. String that contains the name of a task environment variable that should be stored in runenv.

Return values

Because keepenv is a procedure, no return value is set.

Example

In this example, runenv contains the environment variables TERM, CWD, and PS1. All other environment variables are deleted from runenv.

keepenv ("TERM", "CWD", "PS1");

keystrokeactionprofile

Description

The Advanced Keystroke Action component provides advanced control over remote SSH and Telnet sessions.

Syntax

keystrokeactionprofile="profile";

Arguments

profile

Required

A configured Advanced Keystroke Action profile

Return values

None

Example

keystrokeactionprofile="demo";

setenv

Description

The setenv procedure sets the value of an environment variable in runenv.

Syntax

setenv (name, value);

Arguments


name	Required. String that contains the name of the variable to set in runenv.
value	Required. String that contains the value of the specified variable.

Return values

Because setenv is a procedure, no return value is set.

Example

In this example, the SHELL environment variable that is stored in runenv is set to /bin/sh.

setenv ("SHELL", "/bin/sh");

unsetenv

Description

The unsetenv procedure deletes environment variables from runenv.

Syntax

unsetenv (name1 [, name2,…]);

Arguments


name1	Required. A string or a list of character strings that contain the names of runenv environment variables to delete.
name2	Optional. A string or a list of character strings that contain the names of runenv environment variables to delete.

Return values

Because unsetenv is a procedure, no return value is set.

Example

In this example, the runenv environment variables IFS and USER are deleted.

unsetenv ("IFS", "USER");