Python fcntl.fcntl() Examples

def _set_cloexec(self):
        """Set the CLOEXEC flag on all open files (except stdin/out/err).

        If self.max_cloexec_files is an integer (the default), then on
        platforms which support it, it represents the max open files setting
        for the operating system. This function will be called just before
        the process is restarted via os.execv() to prevent open files
        from persisting into the new process.

        Set self.max_cloexec_files to 0 to disable this behavior.
        """
        for fd in range(3, self.max_cloexec_files):  # skip stdin/out/err
            try:
                flags = fcntl.fcntl(fd, fcntl.F_GETFD)
            except IOError:
                continue
            fcntl.fcntl(fd, fcntl.F_SETFD, flags | fcntl.FD_CLOEXEC) 

def read_char_no_blocking():
    ''' Read a character in nonblocking mode, if no characters are present in the buffer, return an empty string '''
    fd = sys.stdin.fileno()
    old_settings = termios.tcgetattr(fd)
    old_flags = fcntl.fcntl(fd, fcntl.F_GETFL)
    try:
        tty.setraw(fd, termios.TCSADRAIN)
        fcntl.fcntl(fd, fcntl.F_SETFL, old_flags | os.O_NONBLOCK)
        return sys.stdin.read(1)
    except IOError as e:
        ErrorNumber = e[0]
        # IOError with ErrorNumber 11(35 in Mac)  is thrown when there is nothing to read(Resource temporarily unavailable)
        if (sys.platform.startswith("linux") and ErrorNumber != 11) or (sys.platform == "darwin" and ErrorNumber != 35):
            raise
        return ""
    finally:
        fcntl.fcntl(fd, fcntl.F_SETFL, old_flags)
        termios.tcsetattr(fd, termios.TCSADRAIN, old_settings) 

def lin_set_ip_address(self, dev, ip, serverip, netmask):
		sockfd = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
		try:
			# set IP
			ifr  = struct.pack('<16sH2s4s8s', dev, socket.AF_INET, "\x00"*2, socket.inet_aton(ip), "\x00"*8)
			fcntl.ioctl(sockfd, self.IOCTL_LINUX_SIOCSIFADDR, ifr)

			# get flags
			ifr = struct.pack('<16sh', dev, 0)
			flags = struct.unpack('<16sh', fcntl.ioctl(sockfd, self.IOCTL_LINUX_SIOCSIFFLAGS, ifr))[1]

			# set new flags
			flags = flags | self.IOCTL_LINUX_IFF_UP
			ifr = struct.pack('<16sh', dev, flags)

			# iface up
			fcntl.ioctl(sockfd, self.IOCTL_LINUX_SIOCSIFFLAGS, ifr)
		except Exception as e:
			common.internal_print("Something went wrong with setting up the interface.", -1)
			print(e)
			sys.exit(-1)

		# adding new route for forwarding packets properly.
		integer_ip = struct.unpack(">I", socket.inet_pton(socket.AF_INET, serverip))[0]
		rangeip = socket.inet_ntop(socket.AF_INET, struct.pack(">I", integer_ip & ((2**int(netmask))-1)<<32-int(netmask)))

		integer_netmask = struct.pack(">I", ((2**int(netmask))-1)<<32-int(netmask))
		netmask = socket.inet_ntoa(integer_netmask)

		ps = subprocess.Popen(["route", "add", "-net", rangeip, "netmask", netmask, "dev", dev], stdout=subprocess.PIPE, stderr=subprocess.PIPE)
		(stdout, stderr) = ps.communicate()
		if stderr:
			if not "File exists" in stderr:
				common.internal_print("Error: adding client route: {0}".format(stderr), -1)
				sys.exit(-1)

		return 

def mac_set_ip_address(self, dev, ip, serverip, netmask):
		ifr = struct.pack('<16sBBHIIIBBHIIIBBHIII',
			self.iface_name,
			16, socket.AF_INET, 0, struct.unpack('<L', socket.inet_pton(socket.AF_INET, ip))[0], 0, 0,
			16, socket.AF_INET, 0, struct.unpack('<L', socket.inet_pton(socket.AF_INET, serverip))[0], 0, 0,
			16, 0, 0, struct.unpack('<L', socket.inet_pton(socket.AF_INET, "255.255.255.255"))[0], 0, 0)
		try:
			sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
			fcntl.ioctl(sock, self.IOCTL_MACOSX_SIOCAIFADDR, ifr)
		except Exception as e:
			common.internal_print("Something went wrong with setting up the interface.", -1)
			print(e)
			sys.exit(-1)

		# adding new route for forwarding packets properly.
		integer_ip = struct.unpack(">I", socket.inet_pton(socket.AF_INET, serverip))[0]
		rangeip = socket.inet_ntop(socket.AF_INET, struct.pack(">I", integer_ip & ((2**int(netmask))-1)<<32-int(netmask)))
		ps = subprocess.Popen(["route", "add", "-net", rangeip+"/"+netmask, serverip], stdout=subprocess.PIPE, stderr=subprocess.PIPE)
		(stdout, stderr) = ps.communicate()
		if stderr:
			if not "File exists" in stderr:
				common.internal_print("Error: adding client route: {0}".format(stderr), -1)
				sys.exit(-1)

		return 

def blocking(self, port, mode=False):
        """
        Set port function mode blocking/nonblocking

        :param port: port to set mode
        :param mode: False to set nonblock mode, True for block mode
        """
        fd = self._open([port])[0]

        try:
            fl = fcntl.fcntl(fd, fcntl.F_GETFL)
            if not mode:
                fcntl.fcntl(fd, fcntl.F_SETFL, fl | os.O_NONBLOCK)
            else:
                fcntl.fcntl(fd, fcntl.F_SETFL, fl & ~os.O_NONBLOCK)

        except Exception as inst:
            print("FAIL: Setting (non)blocking mode: " + str(inst))
            return

        if mode:
            print("PASS: set to blocking mode")
        else:
            print("PASS: set to nonblocking mode") 

def train(self):
        i=0
        if(self.args.ipython):
            import fcntl
            fd = sys.stdin.fileno()
            fl = fcntl.fcntl(fd, fcntl.F_GETFL)
            fcntl.fcntl(fd, fcntl.F_SETFL, fl | os.O_NONBLOCK)

        while((i < self.total_steps or self.total_steps == -1) and not self.gan.destroy):
            i+=1
            start_time = time.time()
            self.step()
            GlobalViewer.tick()

            if (self.args.save_every != None and
                self.args.save_every != -1 and
                self.args.save_every > 0 and
                i % self.args.save_every == 0):
                print(" |= Saving network")
                self.gan.save(self.save_file)
            if self.args.ipython:
                self.check_stdin()
            end_time = time.time() 

def freebsd_tun_alloc(self, dev, flags):
		try:
			sockfd = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
			ifr = struct.pack('<16si', 'tun', 0)
			self.iface_name = fcntl.ioctl(sockfd, self.IOCTL_FREEBSD_SIOCIFCREATE2, ifr)
			self.iface_name = self.iface_name.rstrip("\x00")

			buff = array.array('c', dev+"\x00")
			caddr_t, _ = buff.buffer_info()
			ifr = struct.pack('16sP', self.iface_name, caddr_t);

			fcntl.ioctl(sockfd, self.IOCTL_FREEBSD_SIOCSIFNAME, ifr)
			tun = os.open("/dev/"+self.iface_name, os.O_RDWR | os.O_NONBLOCK)
			self.iface_name = dev

		except IOError as e:
			print e
			common.internal_print("Error: Cannot create tunnel. Is {0} in use?".format(dev), -1)
			sys.exit(-1)

		return tun 

def freebsd_set_ip_address(self, dev, ip, serverip, netmask):
		sockfd = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
		try:
			#set ip, serverip and netmask
			ifaliasreq = struct.pack('<16sBBHI8sBBHI8sBBHI8sI', self.iface_name,
				16, socket.AF_INET, 0, struct.unpack('<I', socket.inet_aton(ip))[0], '\x00'*8,
				16, socket.AF_INET, 0, struct.unpack('<I', socket.inet_aton(serverip))[0], '\x00'*8,
				16, socket.AF_INET, 0, struct.unpack('<I', socket.inet_aton('255.255.255.255'))[0],
				'\x00'*8,
				0)
			fcntl.ioctl(sockfd, self.IOCTL_FREEBSD_SIOCAIFADDR, ifaliasreq)

			# get flags
			ifr = struct.pack('<16sh', self.iface_name, 0)
			flags = struct.unpack('<16sh', fcntl.ioctl(sockfd, self.IOCTL_FREEBSD_SIOCGIFFLAGS, ifr))[1]

			# set new flags
			flags = flags | self.IOCTL_FREEBSD_IFF_UP
			ifr = struct.pack('<16sh', self.iface_name, flags)

			# iface up
			fcntl.ioctl(sockfd, self.IOCTL_FREEBSD_SIOCSIFFLAGS, ifr)
		except Exception as e:
			common.internal_print("Something went wrong with setting up the interface.", -1)
			print(e)
			sys.exit(-1)

		# adding new route for forwarding packets properly.
		integer_ip = struct.unpack(">I", socket.inet_pton(socket.AF_INET, serverip))[0]
		rangeip = socket.inet_ntop(socket.AF_INET, struct.pack(">I", integer_ip & ((2**int(netmask))-1)<<32-int(netmask)))

		ps = subprocess.Popen(["route", "add", "-net", rangeip+"/"+netmask, serverip], stdout=subprocess.PIPE, stderr=subprocess.PIPE)
		(stdout, stderr) = ps.communicate()
		if stderr:
			if not "File exists" in stderr:
				common.internal_print("Error: adding client route: {0}".format(stderr), -1)
				sys.exit(-1)

		return 

def _set_cloexec(fd):
        try:
            flags = _fcntl.fcntl(fd, _fcntl.F_GETFD, 0)
        except IOError:
            pass
        else:
            # flags read successfully, modify
            flags |= _fcntl.FD_CLOEXEC
            _fcntl.fcntl(fd, _fcntl.F_SETFD, flags) 

def prevent_socket_inheritance(sock):
        """Mark the given socket fd as non-inheritable (POSIX)."""
        fd = sock.fileno()
        old_flags = fcntl.fcntl(fd, fcntl.F_GETFD)
        fcntl.fcntl(fd, fcntl.F_SETFD, old_flags | fcntl.FD_CLOEXEC) 

def _set_cloexec_flag(self, fd):
            try:
                cloexec_flag = fcntl.FD_CLOEXEC
            except AttributeError:
                cloexec_flag = 1

            old = fcntl.fcntl(fd, fcntl.F_GETFD)
            fcntl.fcntl(fd, fcntl.F_SETFD, old | cloexec_flag) 

def set_close_exec(fd):
    flags = fcntl.fcntl(fd, fcntl.F_GETFD)
    fcntl.fcntl(fd, fcntl.F_SETFD, flags | fcntl.FD_CLOEXEC) 

def _set_nonblocking(fd):
    flags = fcntl.fcntl(fd, fcntl.F_GETFL)
    fcntl.fcntl(fd, fcntl.F_SETFL, flags | os.O_NONBLOCK) 

def _set_nonblocking(fd: int) -> None:
    flags = fcntl.fcntl(fd, fcntl.F_GETFL)
    fcntl.fcntl(fd, fcntl.F_SETFL, flags | os.O_NONBLOCK) 

def __init__(self, fd, map=None):
            dispatcher.__init__(self, None, map)
            self.connected = True
            try:
                fd = fd.fileno()
            except AttributeError:
                pass
            self.set_file(fd)
            # set it to non-blocking mode
            flags = fcntl.fcntl(fd, fcntl.F_GETFL, 0)
            flags = flags | os.O_NONBLOCK
            fcntl.fcntl(fd, fcntl.F_SETFL, flags) 

def flags(self, *which):
        import fcntl, os

        if which:
            if len(which) > 1:
                raise TypeError, 'Too many arguments'
            which = which[0]
        else: which = '?'

        l_flags = 0
        if 'n' in which: l_flags = l_flags | os.O_NDELAY
        if 'a' in which: l_flags = l_flags | os.O_APPEND
        if 's' in which: l_flags = l_flags | os.O_SYNC

        file = self._file_

        if '=' not in which:
            cur_fl = fcntl.fcntl(file.fileno(), fcntl.F_GETFL, 0)
            if '!' in which: l_flags = cur_fl & ~ l_flags
            else: l_flags = cur_fl | l_flags

        l_flags = fcntl.fcntl(file.fileno(), fcntl.F_SETFL, l_flags)

        if 'c' in which:
            arg = ('!' not in which)    # 0 is don't, 1 is do close on exec
            l_flags = fcntl.fcntl(file.fileno(), fcntl.F_SETFD, arg)

        if '?' in which:
            which = ''                  # Return current flags
            l_flags = fcntl.fcntl(file.fileno(), fcntl.F_GETFL, 0)
            if os.O_APPEND & l_flags: which = which + 'a'
            if fcntl.fcntl(file.fileno(), fcntl.F_GETFD, 0) & 1:
                which = which + 'c'
            if os.O_NDELAY & l_flags: which = which + 'n'
            if os.O_SYNC & l_flags: which = which + 's'
            return which 

def _set_non_blocking(self, fd):
        flags = fcntl.fcntl(fd, fcntl.F_GETFL)
        self.assertNotEqual(flags, -1)
        res = fcntl.fcntl(fd, fcntl.F_SETFL, flags | os.O_NONBLOCK)
        self.assertEqual(res, 0) 

def cmd_run(app, cmd):
    """e.g.: piku run <app> ls -- -al"""

    app = exit_if_invalid(app)

    config_file = join(ENV_ROOT, app, 'LIVE_ENV')
    environ.update(parse_settings(config_file))
    for f in [stdout, stderr]:
        fl = fcntl(f, F_GETFL)
        fcntl(f, F_SETFL, fl | O_NONBLOCK)
    p = Popen(' '.join(cmd), stdin=stdin, stdout=stdout, stderr=stderr, env=environ, cwd=join(APP_ROOT, app), shell=True)
    p.communicate() 

def _set_nonblocking(fd):
    flags = fcntl.fcntl(fd, fcntl.F_GETFL)
    fcntl.fcntl(fd, fcntl.F_SETFL, flags | os.O_NONBLOCK) 

def prevent_socket_inheritance(sock):
            """Dummy function, since neither fcntl nor ctypes are available."""
            pass 

def prevent_socket_inheritance(sock):
        """Mark the given socket fd as non-inheritable (POSIX)."""
        fd = sock.fileno()
        old_flags = fcntl.fcntl(fd, fcntl.F_GETFD)
        fcntl.fcntl(fd, fcntl.F_SETFD, old_flags | fcntl.FD_CLOEXEC) 

def prevent_socket_inheritance(sock):
            """Dummy function, since neither fcntl nor ctypes are available."""
            pass 

def prevent_socket_inheritance(sock):
            """Dummy function, since neither fcntl nor ctypes are available."""
            pass 

def set_close_exec(fd: int) -> None:
    flags = fcntl.fcntl(fd, fcntl.F_GETFD)
    fcntl.fcntl(fd, fcntl.F_SETFD, flags | fcntl.FD_CLOEXEC) 

def _set_non_blocking(self, fd):
        flags = fcntl.fcntl(fd, fcntl.F_GETFL)
        self.assertNotEqual(flags, -1)
        res = fcntl.fcntl(fd, fcntl.F_SETFL, flags | os.O_NONBLOCK)
        self.assertEqual(res, 0) 

def flags(self, *which):
        import fcntl, os

        if which:
            if len(which) > 1:
                raise TypeError, 'Too many arguments'
            which = which[0]
        else: which = '?'

        l_flags = 0
        if 'n' in which: l_flags = l_flags | os.O_NDELAY
        if 'a' in which: l_flags = l_flags | os.O_APPEND
        if 's' in which: l_flags = l_flags | os.O_SYNC

        file = self._file_

        if '=' not in which:
            cur_fl = fcntl.fcntl(file.fileno(), fcntl.F_GETFL, 0)
            if '!' in which: l_flags = cur_fl & ~ l_flags
            else: l_flags = cur_fl | l_flags

        l_flags = fcntl.fcntl(file.fileno(), fcntl.F_SETFL, l_flags)

        if 'c' in which:
            arg = ('!' not in which)    # 0 is don't, 1 is do close on exec
            l_flags = fcntl.fcntl(file.fileno(), fcntl.F_SETFD, arg)

        if '?' in which:
            which = ''                  # Return current flags
            l_flags = fcntl.fcntl(file.fileno(), fcntl.F_GETFL, 0)
            if os.O_APPEND & l_flags: which = which + 'a'
            if fcntl.fcntl(file.fileno(), fcntl.F_GETFD, 0) & 1:
                which = which + 'c'
            if os.O_NDELAY & l_flags: which = which + 'n'
            if os.O_SYNC & l_flags: which = which + 's'
            return which 

def __init__(self, fd, map=None):
            dispatcher.__init__(self, None, map)
            self.connected = True
            try:
                fd = fd.fileno()
            except AttributeError:
                pass
            self.set_file(fd)
            # set it to non-blocking mode
            flags = fcntl.fcntl(fd, fcntl.F_GETFL, 0)
            flags = flags | os.O_NONBLOCK
            fcntl.fcntl(fd, fcntl.F_SETFL, flags) 

def _set_cloexec_flag(self, fd, cloexec=True):
            try:
                cloexec_flag = fcntl.FD_CLOEXEC
            except AttributeError:
                cloexec_flag = 1

            old = fcntl.fcntl(fd, fcntl.F_GETFD)
            if cloexec:
                fcntl.fcntl(fd, fcntl.F_SETFD, old | cloexec_flag)
            else:
                fcntl.fcntl(fd, fcntl.F_SETFD, old & ~cloexec_flag) 

def __init__(self, addr, requestHandler=SimpleXMLRPCRequestHandler,
                 logRequests=True, allow_none=False, encoding=None, bind_and_activate=True):
        self.logRequests = logRequests

        SimpleXMLRPCDispatcher.__init__(self, allow_none, encoding)
        SocketServer.TCPServer.__init__(self, addr, requestHandler, bind_and_activate)

        # [Bug #1222790] If possible, set close-on-exec flag; if a
        # method spawns a subprocess, the subprocess shouldn't have
        # the listening socket open.
        if fcntl is not None and hasattr(fcntl, 'FD_CLOEXEC'):
            flags = fcntl.fcntl(self.fileno(), fcntl.F_GETFD)
            flags |= fcntl.FD_CLOEXEC
            fcntl.fcntl(self.fileno(), fcntl.F_SETFD, flags) 

def _set_cloexec(fd):
        try:
            flags = _fcntl.fcntl(fd, _fcntl.F_GETFD, 0)
        except IOError:
            pass
        else:
            # flags read successfully, modify
            flags |= _fcntl.FD_CLOEXEC
            _fcntl.fcntl(fd, _fcntl.F_SETFD, flags)