envars

Envars, short for environment variables, are a way for software to share information about its environment with other processes. They are dynamic variables that can be set by users, administrators, or programs, and are often used to customize or interact with applications.

Environment variables are stored in the system's memory and are available to any process that wants to access them. They can be used to set configuration options, store user preferences, or pass information between programs. The user or administrator sets the value of an environment variable, and the system manages the variable's storage and retrieval.

Envars are often used in software development to customize the behavior of a program or to interact with external systems. For example, a developer might use an envar to set the location of a database or to select a specific logging configuration. Envars can also be used to build cross-platform applications, where different operating systems have different naming conventions or file locations.

There are different types of envars, including:

* Global variables, which are accessible from anywhere in the system

* Process variables, which are specific to a single process

* User variables, which can be set by a single user

Programs can access envars through built-in functions or apis, which allow them to retrieve or modify variable values. The system provides mechanisms to manage envar values, such as copying, moving and deleting them. The file path, username, and operating system version are common examples of envars. Envars are an essential component of modern computing and are widely used in software development, deployment, and administration.