[Ethereum] How to compile .sol file from the command-line

The geth Javascript console is more adapted to interactive use, when compiling directly with solc, RPC is usually a better choice. To deploy contracts see:

https://github.com/ethereum/wiki/wiki/JSON-RPC#eth_sendtransaction

You can write a simple bash script to compose the json parameter and pass the right data in.

If you are not trying to compile files on the terminal only and can use javascript to do that then this script might help you which I wrote sometime back. I also had multiple dependent contract files which were required to compile the main contract. So I solved using following way -

Define all dependent contracts in an input object keeping the same import order and then use that object to compile your contract.

var input = {
    'strings.sol': fs.readFileSync('strings.sol', 'utf8'),
    'StringLib.sol': fs.readFileSync('StringLib.sol', 'utf8'),
    'Killable.sol': fs.readFileSync('Killable.sol', 'utf8'),
    'Ownable.sol': fs.readFileSync('Ownable.sol', 'utf8'),
    'LMS.sol': fs.readFileSync('LMS.sol', 'utf8')
};
let compiledContract = solc.compile({sources: input}, 1);

Hope this helps.

Note: This requires basic nodejs knowledge.