Java运行时执行

Question

I am trying to execute a docker command from within Java. The docker command needs to be executed in the specified directory.

I found this for executing an external command.

public Process exec(String command, String[] envp, File dir) throws IOException

I am unable to understand what exactly does this envp String array is used for? The documentation reads as:

envp - array of strings, each element of which has environment variable settings in the format name=value, or null if the subprocess should inherit the environment of the current process.

But I am unable to understand what it exactly means in the documentation. Could someone explain it with an example? What exactly do you need to pass as an argument here.

Ps: I am using a *nix environment for dev/deployment.

Answer 1

envp - this is an abbreviation, I guess, from env ironment p arameters (or variables). For instance it can be path to libraries or something else.

If you do not need specify them, than pass it as null

Runtime.getRuntime().exec(command, null, dir);