Module os



os:(command)
Execute the command (a string) in a subshell. This is implemented by calling the Standard C function 
system()
.

os:getenv(name, default = ‘’)
Return the value of the environment variable 
name
if it exists, or 
default
if it doesn't.

os:setenv(name, value)
Set the environment variable named 
name
to the string 
value
.

os:environ
A mapping object representing the string environment.

os:env_path_sep
The character conventionally used by the operating system to separate search path components (as in PATH), such as 
:
for POSIX or 
;
for Windows.