putenvstring

putenvstring is a function often found in C-like programming languages that allows a program to add or modify environment variables. Environment variables are dynamic values that can affect the behavior of processes running on a system. For example, the "PATH" environment variable tells the operating system where to look for executable programs.

When putenvstring is called, it typically takes a string argument in the format "NAME=VALUE". If an environment variable named NAME already exists, its value is updated to VALUE. If NAME does not exist, a new environment variable named NAME with the value VALUE is created. It's important to note that the memory for the environment string is often managed by the program, and its lifetime can be significant.

The exact behavior and availability of putenvstring can vary slightly between different operating systems and programming language implementations. Some systems might have a similar function named setenv, which offers more granular control over variable creation and overwriting. Using putenvstring is a common way for applications to configure themselves dynamically or to pass information to child processes.