Function getenv
Source pub fn getenv(varname: string) -> option<string>
Expand description
Reads an environment variable.
§Parameters
varname: the name of the environment variable.
§Return value
The value of the process environment variable varname, or nil if
the variable is not defined.
§Examples
print(os.getenv("HOME")) --> /home/ana
print(os.getenv("NO_SUCH_VAR")) --> nil