How to Pass Environment Variables to `exec.Command` in Go?
Nov 18, 2024 am 07:15 AMPassing Environment Variables to exec.Command
When creating a wrapper script for a command line tool using exec.Command, you may encounter situations where you need to pass an environment variable as part of the command execution. In this context, you're working with ansible-playbook and require the usage of a parameter MY_VAR.
The exec.Command function accepts an array of strings as its first parameter, where the first element represents the command to execute. To pass an environment variable, we can modify the slice of environment variables in the Cmd struct.
In your case, you're facing issues with overriding all environment variables when using the Env field of the Cmd struct. To address this, you can append the desired environment variable to the existing os.Environ() list:
cmd := exec.Command("ansible-playbook", args...) cmd.Env = os.Environ() cmd.Env = append(cmd.Env, "MY_VAR=some_value")
This approach will preserve the existing environment variables while setting the specific MY_VAR environment variable to your desired value. By combining the native os.Environ() function with the ability to append additional environment variables, you can effectively pass environment variables to your command execution using exec.Command.
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