MX Class

Properties   Methods   Events   Config Settings   Errors  

The MX class enables querying of mail exchange (MX) records from a Domain Name Server (DNS). Thus, it will find out the names of the mail servers accepting email for a given email address or domain.

Syntax

class ipworks.MX

Remarks

The class will attempt to automatically determine the name of a DNS server from the system settings or from the value of the dns_server property.

The class operates in synchronous or asynchronous mode, depending on the value of the timeout property. Calling the resolve method makes the class query the dns_server. The on_response event is fired for each server that handles mail for the email address. The class will fill out the mail_server property with the most preferred mail server and will set the status property to "OK" or to an error message upon completion.

The request_id property may be used to identify requests and is used in the on_response event. The user may set its value before sending out requests and then match the responses to the request using the RequestId parameter in the on_response event.

Property List

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The following is the full list of the properties of the class with short descriptions. Click on the links for further details.

dns_port	This property includes the port where the DNS server is listening.
dns_server	This is the address of the DNS server.
idle	The current status of the class.
local_host	The name of the local host or user-assigned IP interface through which connections are initiated or accepted.
mail_server	This property includes the mail server with the lowest precedence value (lowest cost to reach).
request_id	This property identifies each request.
status	The status of the request is empty while in progress. This property is set to OK or to an error message upon completion.
timeout	A timeout for the class.

Method List

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The following is the full list of the methods of the class with short descriptions. Click on the links for further details.

config	Sets or retrieves a configuration setting.
do_events	Processes events from the internal message queue.
interrupt	Interrupt the current method.
reset	Reset the class.
resolve	This method resolves an email address.

Event List

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The following is the full list of the events fired by the class with short descriptions. Click on the links for further details.

on_error	Information about errors during data delivery.
on_response	This event is fired for each MailServer accepting email for the domain.

Config Settings

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The following is a list of config settings for the class with short descriptions. Click on the links for further details.

CaptureIPPacketInfo	Used to capture the packet information.
DelayHostResolution	Whether the hostname is resolved when RemoteHost is set.
DestinationAddress	Used to get the destination address from the packet information.
DontFragment	Used to set the Don't Fragment flag of outgoing packets.
LocalHost	The name of the local host through which connections are initiated or accepted.
LocalPort	The port in the local host where the class binds.
MaxPacketSize	The maximum length of the packets that can be received.
QOSDSCPValue	Used to specify an arbitrary QOS/DSCP setting (optional).
QOSTrafficType	Used to specify QOS/DSCP settings (optional).
ShareLocalPort	If set to True, allows more than one instance of the class to be active on the same local port.
SourceIPAddress	Used to set the source IP address used when sending a packet.
SourceMacAddress	Used to set the source MAC address used when sending a packet.
UseConnection	Determines whether to use a connected socket.
UseIPv6	Whether or not to use IPv6.
AbsoluteTimeout	Determines whether timeouts are inactivity timeouts or absolute timeouts.
FirewallData	Used to send extra data to the firewall.
InBufferSize	The size in bytes of the incoming queue of the socket.
OutBufferSize	The size in bytes of the outgoing queue of the socket.
BuildInfo	Information about the product's build.
CodePage	The system code page used for Unicode to Multibyte translations.
LicenseInfo	Information about the current license.
MaskSensitive	Whether sensitive data is masked in log messages.
ProcessIdleEvents	Whether the class uses its internal event loop to process events when the main thread is idle.
SelectWaitMillis	The length of time in milliseconds the class will wait when DoEvents is called if there are no events to process.
UseInternalSecurityAPI	Tells the class whether or not to use the system security libraries or an internal implementation.

dns_port Property

This property includes the port where the DNS server is listening.

Syntax

def get_dns_port() -> int: ...
def set_dns_port(value: int) -> None: ...

dns_port = property(get_dns_port, set_dns_port)

Default Value

53

Remarks

This property contains the port where the DNS server is listening. The default value is 53, but you may set this property to any other value for use with experimental servers and such.

dns_server Property

This is the address of the DNS server.

Syntax

def get_dns_server() -> str: ...
def set_dns_server(value: str) -> None: ...

dns_server = property(get_dns_server, set_dns_server)

Default Value

""

Remarks

This property contains the address of the DNS server. The class attempts to find the default DNS server for the machine where it is installed, and provide it in the dns_server property. You may change it to any particular DNS server you want to query. While any internet host running a DNS service will suffice, it is preferable to use either the DNS server for your network or the DNS server for the domain that you are querying.

If the class cannot determine the default DNS server address, the property value will be an empty string.

Note: Automatic discovery of the default DNS server is not supported in the Java edition.

idle Property

The current status of the class.

Syntax

def get_idle() -> bool: ...

idle = property(get_idle, None)

Default Value

TRUE

Remarks

idle will be False if the component is currently busy (communicating and/or waiting for an answer), and True at all other times.

This property is read-only.

local_host Property

The name of the local host or user-assigned IP interface through which connections are initiated or accepted.

Syntax

def get_local_host() -> str: ...
def set_local_host(value: str) -> None: ...

local_host = property(get_local_host, set_local_host)

Default Value

""

Remarks

The local_host property contains the name of the local host as obtained by the gethostname() system call, or if the user has assigned an IP address, the value of that address.

In multi-homed hosts (machines with more than one IP interface) setting LocalHost to the value of an interface will make the class initiate connections (or accept in the case of server classs) only through that interface.

If the class is connected, the local_host property shows the IP address of the interface through which the connection is made in internet dotted format (aaa.bbb.ccc.ddd). In most cases, this is the address of the local host, except for multi-homed hosts (machines with more than one IP interface).

NOTE: local_host is not persistent. You must always set it in code, and never in the property window.

mail_server Property

This property includes the mail server with the lowest precedence value (lowest cost to reach).

Syntax

def get_mail_server() -> str: ...

mail_server = property(get_mail_server, None)

Default Value

""

Remarks

This property contains the mail server with lowest precedence value (lowest cost to reach). After all events are fired, this property holds the name of the best mail server for the supplied email address, and the status property holds the completion status.

This property is read-only.

request_id Property

This property identifies each request.

Syntax

def get_request_id() -> int: ...
def set_request_id(value: int) -> None: ...

request_id = property(get_request_id, set_request_id)

Default Value

0

Remarks

This property identifies each request. This may be useful if several email addresses need to be resolved. Each request may be identified by the user before starting a query by calling the resolve method.

If a custom value is needed for request_id, the property must be set before resolving an email address. The class increments request_id automatically after sending each request.

status Property

The status of the request is empty while in progress. This property is set to OK or to an error message upon completion.

Syntax

def get_status() -> str: ...

status = property(get_status, None)

Default Value

""

Remarks

This property is reset each time the resolve method is called. When a response comes from the dns_server, this property is set to "OK" in case of success or to an error message as described in the on_response event.

This property is read-only.

timeout Property

A timeout for the class.

Syntax

def get_timeout() -> int: ...
def set_timeout(value: int) -> None: ...

timeout = property(get_timeout, set_timeout)

Default Value

60

Remarks

If the timeout property is set to 0, all operations return immediately, potentially failing with a WOULDBLOCK error if data cannot be sent immediately.

If timeout is set to a positive value, data is sent in a blocking manner and the class will wait for the operation to complete before returning control. The class will handle any potential WOULDBLOCK errors internally and automatically retry the operation for a maximum of timeout seconds.

The class will use do_events to enter an efficient wait loop during any potential waiting period, making sure that all system events are processed immediately as they arrive. This ensures that the host application does not "freeze" and remains responsive.

If timeout expires, and the operation is not yet complete, the class fails with an error.

Please note that by default, all timeouts are inactivity timeouts, i.e. the timeout period is extended by timeout seconds when any amount of data is successfully sent or received.

The default value for the timeout property is 60 seconds.

config Method

Sets or retrieves a configuration setting.

Syntax

def config(configuration_string: str) -> str: ...

Remarks

config is a generic method available in every class. It is used to set and retrieve configuration settings for the class.

These settings are similar in functionality to properties, but they are rarely used. In order to avoid "polluting" the property namespace of the class, access to these internal properties is provided through the config method.

To set a configuration setting named PROPERTY, you must call Config("PROPERTY=VALUE"), where VALUE is the value of the setting expressed as a string. For boolean values, use the strings "True", "False", "0", "1", "Yes", or "No" (case does not matter).

To read (query) the value of a configuration setting, you must call Config("PROPERTY"). The value will be returned as a string.

do_events Method

Processes events from the internal message queue.

Syntax

def do_events() -> None: ...

Remarks

When do_events is called, the class processes any available events. If no events are available, it waits for a preset period of time, and then returns.

interrupt Method

Interrupt the current method.

Syntax

def interrupt() -> None: ...

Remarks

If there is no method in progress, interrupt simply returns, doing nothing.

reset Method

Reset the class.

Syntax

def reset() -> None: ...

Remarks

This method will reset the class's properties to their default values.

resolve Method

This method resolves an email address.

Syntax

def resolve(email_address: str) -> None: ...

Remarks

This method resolves an email address. Calling this method directs the class to query dns_server at port dns_port about MX records related to EmailAddress.

The server's response is provided through one or more on_response events.

After the query completes, the mail_server property is set to the best mail server and the status property includes the result description of the response.

Valid queries are email addresses like name@company.com or hostnames and domains like domain.com.

Example. Determine Top Priority Mail Server of Email Address:

MXControl.Resolve "email@server.com" While MXControl.MailServer = "" MXControl.DoEvents() End While BestMailServer = MXControl.MailServer

on_error Event

Information about errors during data delivery.

Syntax

class MXErrorEventParams(object):
  @property
  def error_code() -> int: ...

  @property
  def description() -> str: ...

# In class MX:
@property
def on_error() -> Callable[[MXErrorEventParams], None]: ...
@on_error.setter
def on_error(event_hook: Callable[[MXErrorEventParams], None]) -> None: ...

Remarks

The on_error event is fired in case of exceptional conditions during message processing. Normally the class fails with an error.

ErrorCode contains an error code and Description contains a textual description of the error. For a list of valid error codes and their descriptions, please refer to the Error Codes section.

on_response Event

This event is fired for each MailServer accepting email for the domain.

Syntax

class MXResponseEventParams(object):
  @property
  def request_id() -> int: ...

  @property
  def domain() -> str: ...

  @property
  def mail_server() -> str: ...

  @property
  def precedence() -> int: ...

  @property
  def time_to_live() -> int: ...

  @property
  def status_code() -> int: ...

  @property
  def description() -> str: ...

  @property
  def authoritative() -> bool: ...

# In class MX:
@property
def on_response() -> Callable[[MXResponseEventParams], None]: ...
@on_response.setter
def on_response(event_hook: Callable[[MXResponseEventParams], None]) -> None: ...

Remarks

A on_response event is fired for each mail server handling email for the requested domain. The RequestId parameter identifies the request and equals the value of request_id property right before the resolve method is called. MailServer is the name of the server handling the email for the requested Domain. A lower Precedence value should be preferred. The TimeToLive parameter gives the validity time in seconds before the dns_server should be queried again.

Possible values for the StatusCode and Description parameters are as follows:

StatusCode	Description
0	Ok
1	Format error
2	Server failure
3	Name error
4	Not implemented
5	Refused

After the last on_response event is fired, the class sets the mail_server and status properties to the best MailServer and the error or success code, respectively.

MX Config Settings

The class accepts one or more of the following configuration settings. Configuration settings are similar in functionality to properties, but they are rarely used. In order to avoid "polluting" the property namespace of the class, access to these internal properties is provided through the config method.

UDP Config Settings

CaptureIPPacketInfo:   Used to capture the packet information. If this is set to true, the component will capture the IP packet information. The default value for this setting is False. Note: This setting is only available in Windows.

DelayHostResolution:   Whether the hostname is resolved when RemoteHost is set. This setting specifies whether a hostname is resolved immediately when remote_host is set. If True the class will resolve the hostname and the IP address will be present in the remote_host property. If False, the hostname is not resolved until needed by the component when a method to connect or send data is called. If desired, resolve_remote_host may called to manually resolve the value in remote_host at any time. The default value is False.

DestinationAddress:   Used to get the destination address from the packet information. If CaptureIPPacketInfo is set to true, then this will be populated with the packet's destination address when a packet is received. This information will be accessible in the DataIn event. Note: This setting is only available in Windows.

DontFragment:   Used to set the Don't Fragment flag of outgoing packets. When set to True, packets sent by the class will have the Don't Fragment flag set. The default value is False.

LocalHost:   The name of the local host through which connections are initiated or accepted. The local_host setting contains the name of the local host as obtained by the gethostname() system call, or if the user has assigned an IP address, the value of that address. In multi-homed hosts (machines with more than one IP interface) setting LocalHost to the value of an interface will make the class initiate connections (or accept in the case of server classs) only through that interface. If the class is connected, the local_host setting shows the IP address of the interface through which the connection is made in internet dotted format (aaa.bbb.ccc.ddd). In most cases, this is the address of the local host, except for multi-homed hosts (machines with more than one IP interface).

LocalPort:   The port in the local host where the class binds. This must be set before a connection is attempted. It instructs the class to bind to a specific port (or communication endpoint) in the local machine. Setting this to 0 (default) enables the system to choose a port at random. The chosen port will be shown by local_port after the connection is established. local_port cannot be changed once a connection is made. Any attempt to set this when a connection is active will generate an error. This; setting is useful when trying to connect to services that require a trusted port in the client side. An example is the remote shell (rsh) service in UNIX systems.

MaxPacketSize:   The maximum length of the packets that can be received. This setting specifies the maximum size of the datagrams that the class will accept without truncation.

QOSDSCPValue:   Used to specify an arbitrary QOS/DSCP setting (optional). UseConnection must be True to use this setting. This option allows you to specify an arbitrary DSCP value between 0 and 63. The default is 0. When set to the default value the component will not set a DSCP value. Note: This setting uses the qWAVE API is only available on Windows 7, Windows Server 2008 R2, and later.

QOSTrafficType:   Used to specify QOS/DSCP settings (optional). UseConnection must be True to use this setting. You may specify either the text or integer values: BestEffort (0), Background (1), ExcellentEffort (2), AudioVideo (3), Voice (4), and Control (5). Note: This setting uses the qWAVE API which is only available on Windows Vista and Windows Server 2008 or above. Note: QOSTrafficType must be set before setting active to true.

ShareLocalPort:   If set to True, allows more than one instance of the class to be active on the same local port. This option must be set before the class is activated through the active property or it will have no effect. The default value for this setting is False.

SourceIPAddress:   Used to set the source IP address used when sending a packet. This configuration setting can be used to override the source IP address when sending a packet. Note: This setting is only available in Windows and requires that the winpcap library be installed (or npcap with winpcap compatibility).

SourceMacAddress:   Used to set the source MAC address used when sending a packet. This configuration setting can be used to override the source MAC address when sending a packet. Note: This setting is only available in Windows and requires that the winpcap library be installed (or npcap with winpcap compatibility).

UseConnection:   Determines whether to use a connected socket. UseConnection specifies whether the class should use a connected socket or not. The connection is defined as an association in between the local address/port and the remote address/port. As such, this is not a connection in the traditional TCP sense. What it means is only that the class will send and receive data only to and from the specified destination. The default value for this setting is False.

UseIPv6:   Whether or not to use IPv6. By default, the component expects an IPv4 address for local and remote host properties, and will create an IPv4 socket. To use IPv6 instead, set this to True.

Socket Config Settings

AbsoluteTimeout:   Determines whether timeouts are inactivity timeouts or absolute timeouts. If AbsoluteTimeout is set to True, any method which does not complete within Timeout seconds will be aborted. By default, AbsoluteTimeout is False, and the timeout is an inactivity timeout. Note: This option is not valid for UDP ports.

FirewallData:   Used to send extra data to the firewall. When the firewall is a tunneling proxy, use this property to send custom (additional) headers to the firewall (e.g. headers for custom authentication schemes).

InBufferSize:   The size in bytes of the incoming queue of the socket. This is the size of an internal queue in the TCP/IP stack. You can increase or decrease its size depending on the amount of data that you will be receiving. Increasing the value of the InBufferSize setting can provide significant improvements in performance in some cases. Some TCP/IP implementations do not support variable buffer sizes. If that is the case, when the class is activated the InBufferSize reverts to its defined size. The same happens if you attempt to make it too large or too small.

OutBufferSize:   The size in bytes of the outgoing queue of the socket. This is the size of an internal queue in the TCP/IP stack. You can increase or decrease its size depending on the amount of data that you will be sending. Increasing the value of the OutBufferSize setting can provide significant improvements in performance in some cases. Some TCP/IP implementations do not support variable buffer sizes. If that is the case, when the class is activated the OutBufferSize reverts to its defined size. The same happens if you attempt to make it too large or too small.

Base Config Settings

BuildInfo:   Information about the product's build. When queried, this setting will return a string containing information about the product's build.

CodePage:   The system code page used for Unicode to Multibyte translations. The default code page is Unicode UTF-8 (65001). The following is a list of valid code page identifiers: Identifier Name 037 IBM EBCDIC - U.S./Canada 437 OEM - United States 500 IBM EBCDIC - International 708 Arabic - ASMO 708 709 Arabic - ASMO 449+, BCON V4 710 Arabic - Transparent Arabic 720 Arabic - Transparent ASMO 737 OEM - Greek (formerly 437G) 775 OEM - Baltic 850 OEM - Multilingual Latin I 852 OEM - Latin II 855 OEM - Cyrillic (primarily Russian) 857 OEM - Turkish 858 OEM - Multilingual Latin I + Euro symbol 860 OEM - Portuguese 861 OEM - Icelandic 862 OEM - Hebrew 863 OEM - Canadian-French 864 OEM - Arabic 865 OEM - Nordic 866 OEM - Russian 869 OEM - Modern Greek 870 IBM EBCDIC - Multilingual/ROECE (Latin-2) 874 ANSI/OEM - Thai (same as 28605, ISO 8859-15) 875 IBM EBCDIC - Modern Greek 932 ANSI/OEM - Japanese, Shift-JIS 936 ANSI/OEM - Simplified Chinese (PRC, Singapore) 949 ANSI/OEM - Korean (Unified Hangul Code) 950 ANSI/OEM - Traditional Chinese (Taiwan; Hong Kong SAR, PRC) 1026 IBM EBCDIC - Turkish (Latin-5) 1047 IBM EBCDIC - Latin 1/Open System 1140 IBM EBCDIC - U.S./Canada (037 + Euro symbol) 1141 IBM EBCDIC - Germany (20273 + Euro symbol) 1142 IBM EBCDIC - Denmark/Norway (20277 + Euro symbol) 1143 IBM EBCDIC - Finland/Sweden (20278 + Euro symbol) 1144 IBM EBCDIC - Italy (20280 + Euro symbol) 1145 IBM EBCDIC - Latin America/Spain (20284 + Euro symbol) 1146 IBM EBCDIC - United Kingdom (20285 + Euro symbol) 1147 IBM EBCDIC - France (20297 + Euro symbol) 1148 IBM EBCDIC - International (500 + Euro symbol) 1149 IBM EBCDIC - Icelandic (20871 + Euro symbol) 1200 Unicode UCS-2 Little-Endian (BMP of ISO 10646) 1201 Unicode UCS-2 Big-Endian 1250 ANSI - Central European 1251 ANSI - Cyrillic 1252 ANSI - Latin I 1253 ANSI - Greek 1254 ANSI - Turkish 1255 ANSI - Hebrew 1256 ANSI - Arabic 1257 ANSI - Baltic 1258 ANSI/OEM - Vietnamese 1361 Korean (Johab) 10000 MAC - Roman 10001 MAC - Japanese 10002 MAC - Traditional Chinese (Big5) 10003 MAC - Korean 10004 MAC - Arabic 10005 MAC - Hebrew 10006 MAC - Greek I 10007 MAC - Cyrillic 10008 MAC - Simplified Chinese (GB 2312) 10010 MAC - Romania 10017 MAC - Ukraine 10021 MAC - Thai 10029 MAC - Latin II 10079 MAC - Icelandic 10081 MAC - Turkish 10082 MAC - Croatia 12000 Unicode UCS-4 Little-Endian 12001 Unicode UCS-4 Big-Endian 20000 CNS - Taiwan 20001 TCA - Taiwan 20002 Eten - Taiwan 20003 IBM5550 - Taiwan 20004 TeleText - Taiwan 20005 Wang - Taiwan 20105 IA5 IRV International Alphabet No. 5 (7-bit) 20106 IA5 German (7-bit) 20107 IA5 Swedish (7-bit) 20108 IA5 Norwegian (7-bit) 20127 US-ASCII (7-bit) 20261 T.61 20269 ISO 6937 Non-Spacing Accent 20273 IBM EBCDIC - Germany 20277 IBM EBCDIC - Denmark/Norway 20278 IBM EBCDIC - Finland/Sweden 20280 IBM EBCDIC - Italy 20284 IBM EBCDIC - Latin America/Spain 20285 IBM EBCDIC - United Kingdom 20290 IBM EBCDIC - Japanese Katakana Extended 20297 IBM EBCDIC - France 20420 IBM EBCDIC - Arabic 20423 IBM EBCDIC - Greek 20424 IBM EBCDIC - Hebrew 20833 IBM EBCDIC - Korean Extended 20838 IBM EBCDIC - Thai 20866 Russian - KOI8-R 20871 IBM EBCDIC - Icelandic 20880 IBM EBCDIC - Cyrillic (Russian) 20905 IBM EBCDIC - Turkish 20924 IBM EBCDIC - Latin-1/Open System (1047 + Euro symbol) 20932 JIS X 0208-1990 & 0121-1990 20936 Simplified Chinese (GB2312) 21025 IBM EBCDIC - Cyrillic (Serbian, Bulgarian) 21027 Extended Alpha Lowercase 21866 Ukrainian (KOI8-U) 28591 ISO 8859-1 Latin I 28592 ISO 8859-2 Central Europe 28593 ISO 8859-3 Latin 3 28594 ISO 8859-4 Baltic 28595 ISO 8859-5 Cyrillic 28596 ISO 8859-6 Arabic 28597 ISO 8859-7 Greek 28598 ISO 8859-8 Hebrew 28599 ISO 8859-9 Latin 5 28605 ISO 8859-15 Latin 9 29001 Europa 3 38598 ISO 8859-8 Hebrew 50220 ISO 2022 Japanese with no halfwidth Katakana 50221 ISO 2022 Japanese with halfwidth Katakana 50222 ISO 2022 Japanese JIS X 0201-1989 50225 ISO 2022 Korean 50227 ISO 2022 Simplified Chinese 50229 ISO 2022 Traditional Chinese 50930 Japanese (Katakana) Extended 50931 US/Canada and Japanese 50933 Korean Extended and Korean 50935 Simplified Chinese Extended and Simplified Chinese 50936 Simplified Chinese 50937 US/Canada and Traditional Chinese 50939 Japanese (Latin) Extended and Japanese 51932 EUC - Japanese 51936 EUC - Simplified Chinese 51949 EUC - Korean 51950 EUC - Traditional Chinese 52936 HZ-GB2312 Simplified Chinese 54936 Windows XP: GB18030 Simplified Chinese (4 Byte) 57002 ISCII Devanagari 57003 ISCII Bengali 57004 ISCII Tamil 57005 ISCII Telugu 57006 ISCII Assamese 57007 ISCII Oriya 57008 ISCII Kannada 57009 ISCII Malayalam 57010 ISCII Gujarati 57011 ISCII Punjabi 65000 Unicode UTF-7 65001 Unicode UTF-8 The following is a list of valid code page identifiers for Mac OS only: Identifier Name 1 ASCII 2 NEXTSTEP 3 JapaneseEUC 4 UTF8 5 ISOLatin1 6 Symbol 7 NonLossyASCII 8 ShiftJIS 9 ISOLatin2 10 Unicode 11 WindowsCP1251 12 WindowsCP1252 13 WindowsCP1253 14 WindowsCP1254 15 WindowsCP1250 21 ISO2022JP 30 MacOSRoman 10 UTF16String 0x90000100 UTF16BigEndian 0x94000100 UTF16LittleEndian 0x8c000100 UTF32String 0x98000100 UTF32BigEndian 0x9c000100 UTF32LittleEndian 65536 Proprietary

LicenseInfo:   Information about the current license. When queried, this setting will return a string containing information about the license this instance of a class is using. It will return the following information: Product: The product the license is for. Product Key: The key the license was generated from. License Source: Where the license was found (e.g., RuntimeLicense, License File). License Type: The type of license installed (e.g., Royalty Free, Single Server). Last Valid Build: The last valid build number for which the license will work.

MaskSensitive:   Whether sensitive data is masked in log messages. In certain circumstances it may be beneficial to mask sensitive data, like passwords, in log messages. Set this to True to mask sensitive data. The default is False. This setting only works on these classes: AS3Receiver, AS3Sender, Atom, Client(3DS), FTP, FTPServer, IMAP, OFTPClient, SSHClient, SCP, Server(3DS), Sexec, SFTP, SFTPServer, SSHServer, TCPClient, TCPServer.

ProcessIdleEvents:   Whether the class uses its internal event loop to process events when the main thread is idle. If set to False, the class will not fire internal idle events. Set this to False to use the class in a background thread on Mac OS. By default, this setting is True.

SelectWaitMillis:   The length of time in milliseconds the class will wait when DoEvents is called if there are no events to process. If there are no events to process when do_events is called, the class will wait for the amount of time specified here before returning. The default value is 20.

UseInternalSecurityAPI:   Tells the class whether or not to use the system security libraries or an internal implementation. When set to False, the class will use the system security libraries by default to perform cryptographic functions where applicable. Setting this setting to True tells the class to use the internal implementation instead of using the system security libraries. On Windows, this setting is set to False by default. On Linux/macOS, this setting is set to True by default. To use the system security libraries for Linux, OpenSSL support must be enabled. For more information on how to enable OpenSSL, please refer to the OpenSSL Notes section.

MX Errors

MX Errors

	290   No DNS server specified.
	530   Busy performing current action.

The class may also return one of the following error codes, which are inherited from other classes.

UDP Errors

	104   UDP is already active.
	106   You cannot change the local_port while the class is active.
	107   You cannot change the local_host at this time. A connection is in progress.
	109   The class must be active for this operation.
	112   Cannot change MaxPacketSize while the class is active.
	113   Cannot change ShareLocalPort option while the class is active.
	114   Cannot change remote_host when UseConnection is set and the class active.
	115   Cannot change remote_port when UseConnection is set and the class is active.
	116   remote_port can't be zero when UseConnection is set. Please specify a valid service port number.
	117   Cannot change UseConnection while the class is active.
	118   Message can't be longer than MaxPacketSize.
	119   Message too short.
	434   Unable to convert string to selected CodePage

SSL Errors

	270   Cannot load specified security library.
	271   Cannot open certificate store.
	272   Cannot find specified certificate.
	273   Cannot acquire security credentials.
	274   Cannot find certificate chain.
	275   Cannot verify certificate chain.
	276   Error during handshake.
	280   Error verifying certificate.
	281   Could not find client certificate.
	282   Could not find server certificate.
	283   Error encrypting data.
	284   Error decrypting data.

TCP/IP Errors

	10004   [10004] Interrupted system call.
	10009   [10009] Bad file number.
	10013   [10013] Access denied.
	10014   [10014] Bad address.
	10022   [10022] Invalid argument.
	10024   [10024] Too many open files.
	10035   [10035] Operation would block.
	10036   [10036] Operation now in progress.
	10037   [10037] Operation already in progress.
	10038   [10038] Socket operation on non-socket.
	10039   [10039] Destination address required.
	10040   [10040] Message too long.
	10041   [10041] Protocol wrong type for socket.
	10042   [10042] Bad protocol option.
	10043   [10043] Protocol not supported.
	10044   [10044] Socket type not supported.
	10045   [10045] Operation not supported on socket.
	10046   [10046] Protocol family not supported.
	10047   [10047] Address family not supported by protocol family.
	10048   [10048] Address already in use.
	10049   [10049] Can't assign requested address.
	10050   [10050] Network is down.
	10051   [10051] Network is unreachable.
	10052   [10052] Net dropped connection or reset.
	10053   [10053] Software caused connection abort.
	10054   [10054] Connection reset by peer.
	10055   [10055] No buffer space available.
	10056   [10056] Socket is already connected.
	10057   [10057] Socket is not connected.
	10058   [10058] Can't send after socket shutdown.
	10059   [10059] Too many references, can't splice.
	10060   [10060] Connection timed out.
	10061   [10061] Connection refused.
	10062   [10062] Too many levels of symbolic links.
	10063   [10063] File name too long.
	10064   [10064] Host is down.
	10065   [10065] No route to host.
	10066   [10066] Directory not empty
	10067   [10067] Too many processes.
	10068   [10068] Too many users.
	10069   [10069] Disc Quota Exceeded.
	10070   [10070] Stale NFS file handle.
	10071   [10071] Too many levels of remote in path.
	10091   [10091] Network subsystem is unavailable.
	10092   [10092] WINSOCK DLL Version out of range.
	10093   [10093] Winsock not loaded yet.
	11001   [11001] Host not found.
	11002   [11002] Non-authoritative 'Host not found' (try again or check DNS setup).
	11003   [11003] Non-recoverable errors: FORMERR, REFUSED, NOTIMP.
	11004   [11004] Valid name, no data record (check DNS setup).