wsh.js/lib/cmds/head.js

WebSHell provides a toolkit for building bash-like command line consoles for web pages.

export default {
    desc: "Show first lines",
    args: [ "?count" ],
    exec: async (term, streams, cmd, opts, args) => {
        let data;
        let count = args.count || 10;

        while ((data = await streams.stdin.read()) !== false && count > 0) {
            await streams.stdout.write(data);
            count--;
        }
    }
};