plaster._inlet

def _inlet():
    '''
    Reads file in one of four ways: argument, Xclip, input, and stdin. 
    Returns content in bytes.
    '''
    try:
        ## Optional clipboard feature.
        if args.Xclip:
            if not pyperclip:
                exit('e: missing python-pyperclip')
            if not args.force:
                print('plaster your clipboard for all to see?')
                exit('add -f')
            content = bytes(pyperclip.paste(), 'utf-8')
        elif [condition where stdin is True]
            content = stdin.buffer.read()
        else:
            if args.content:
                content_path = args.content
            ## measures no arguments or options.
            elif isatty(0):
                print('enter a file to plaster')
                content_path = input('$ ')
            with open(content_path, 'rb') as i:
                content = i.read()
        return content
    except KeyboardInterrupt:
        print()
        exit('for help, try: plaster -h')
    except Exception as e:
        print('e: inlet:', e)
        exit(1)