To spawn a command interpreter and execute a command use
unix(shell(+Command)). The reference page for unix/1
contains examples. If Command is an atom, a new shell process
is invoked, and Command is passed to it for execution as a
shell command. Under UNIX, the shell invoked depends on your SHELL environment
variable.
Under Windows, the default shell is used, as determined by the
system() C library function.
If the shell returns with a non-zero result (for example,
because the command was not found), unix(shell(Command))
simply fails.
Similarly, a new standard shell process can be invoked by calling
unix(system(+Command)). The standard shell is
sh(1) under UNIX and as determined by the
system() C library function under Windows.