pub fn command_line(input: &BStr) -> Result<Outcome, Error>Expand description
Split input into leading environment assignments and the command with its arguments.
Whitespace, quotes, escapes, line continuations, and comments follow POSIX shell word-splitting rules. Shell
expansions and operators are not interpreted. An assignment is recognized only when its name is an unquoted
shell identifier. Assignment-only input is rejected because it contains no command to execute. Environment
assignment names are strings, while their values, the command, and arguments are converted losslessly to OS
strings or rejected if the platform cannot represent them.