# ZCompress Class

The ZCompress class implements an LZC compressor and decompressor. It is compatible with the UNIX compress utility.

## Syntax

```text
class ipworkszip.ZCompress
```

## Remarks

The LZC file format is used only to archive a single file. Accordingly, the operation of the class is simpler than that of the other classes.

To compress with the class, set [archive_file](#archive_file-property) to the name of the LZC compressed file to be created, and [file_decompressed_name](#file_decompressed_name-property) to the name of the file to be compressed. Finally, invoke [compress](#compress-method). To extract the file, first set [archive_file](#archive_file-property). [file_decompressed_name](#file_decompressed_name-property) may then be set; if not, it will automatically be set based on the [archive_file](#archive_file-property) name. Finally, invoke the [extract](#extract-method) method.

**Example (Creating an LZC File)**

```text
ZipControl.ArchiveFile = "c:\test.Z"
ZipControl.FileDecompressedName = "c:\test.txt"
ZipControl.Compress()
```

 **Example (Extracting from an LZC File)**

```text
ZipControl.ArchiveFile = "c:\test.Z"
ZipControl.FileDecompressedName = "c:\test.txt"
ZipControl.Extract()
```

## Property List

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

|  |  |
| --- | --- |
| [archive_file](#archive_file-property) | The name of the zip, gzip, tar, or jar archive. |
| [file_decompressed_name](#file_decompressed_name-property) | File name to decompress to, or compress from. |
| [file_input_data](#file_input_data-property) | The data of the file to be compressed. |
| [z_compress_data](#z_compress_data-property) | (Decompression only) The LZC compressed file contents as a byte array. |

## Method List

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

|  |  |
| --- | --- |
| [abort](#abort-method) | Aborts the current operation. |
| [compress](#compress-method) | Creates the compressed archive. |
| [config](#config-method) | Sets or retrieves a configuration setting. |
| [extract](#extract-method) | Extracts the compressed file from the archive. |
| [reset](#reset-method) | Resets the class. |

## Event List

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

|  |  |
| --- | --- |
| [on_begin_file](#on_begin_file-event) | Fired before a file is processed. |
| [on_end_file](#on_end_file-event) | Fired after a file is processed. |
| [on_error](#on_error-event) | Information about non-fatal errors. |
| [on_overwrite](#on_overwrite-event) | Fired whenever a file exists and may be overwritten. |
| [on_progress](#on_progress-event) | Fired as progress is made. |

## Config Settings

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

|  |  |
| --- | --- |
| [WriteToProgressEvent](#WriteToProgressEvent) | Whether or not to write data to the Progress Event. |
| [BuildInfo](#BuildInfo) | Information about the product's build. |
| [CodePage](#CodePage) | The system code page used for Unicode to Multibyte translations. |
| [LicenseInfo](#LicenseInfo) | Information about the current license. |
| [MaskSensitiveData](#MaskSensitiveData) | Whether sensitive data is masked in log messages. |
| [ProcessIdleEvents](#ProcessIdleEvents) | Whether the class uses its internal event loop to process events when the main thread is idle. |
| [SelectWaitMillis](#SelectWaitMillis) | The length of time in milliseconds the class will wait when DoEvents is called if there are no events to process. |
| [UseInternalSecurityAPI](#UseInternalSecurityAPI) | Whether or not to use the system security libraries or an internal implementation. |

# archive_file property

The name of the zip, gzip, tar, or jar archive.

## Syntax

```text
def get_archive_file() -> str: ...
def set_archive_file(value: str) -> None: ...
archive_file = property(get_archive_file, set_archive_file)
```

## Default Value

""

## Remarks

This property specifies the name of the archive to be read or written. This property is required when extracting files.

When scan, [extract](#extract-method), or extract_all is invoked, the file specified by archive_file will be opened for read. If the file does not exist, a trappable error will be generated.

When [compress](#compress-method) is called, the file named by archive_file will be written; if a file of this name already exists the [on_overwrite](#on_overwrite-event) event will be fired. If archive_file is set to the empty string (""), the archive will not be written to disk, and will be provided only through the [on_progress](#on_progress-event) event.

The filename may be specified with or without a path. Paths may be relative or absolute, and should be specified in the format native to the host operating system. The filename should be specified with the appropriate extension (such as "zip"); an extension will not automatically be appended by the class.

If the file cannot be read, or written, as appropriate, a trappable error will be generated.

**Example (Creating an Archive)**

```text
ZipControl.ArchiveFile = "c:\test.zip"
ZipControl.RecurseSubdirectories = true
ZipControl.IncludeFiles("c:\foo\*")
ZipControl.Compress()
```

NOTE: an archive already open for read may be closed by setting archive_file to the empty string ("").

# file_decompressed_name property

File name to decompress to, or compress from.

## Syntax

```text
def get_file_decompressed_name() -> str: ...
def set_file_decompressed_name(value: str) -> None: ...
file_decompressed_name = property(get_file_decompressed_name, set_file_decompressed_name)
```

## Default Value

""

## Remarks

file_decompressed_name contains the name of the file in the archive, as stored on the file system, outside the archive.

When compressing a file and set_file_input_stream has not been called with a valid input stream, this property should be specified with a path, if necessary, to allow the file to be found by the class. If the file cannot be found when [compress](#compress-method) is called, a trappable error will be generated, and the archive will not be correctly written.

When decompressing files, this property may be set prior to calling [extract](#extract-method). If this property is set to the empty string when [extract](#extract-method) is called, [extract](#extract-method) will automatically set this property to an appropriate value.

 Paths on the local file system should be specified in the format native to the host operating system. They may also be specified in standard (UNIX) format, in which case they will be immediately converted.

# file_input_data property

The data of the file to be compressed.

## Syntax

```text
def get_file_input_data() -> bytes: ...
def set_file_input_data(value: bytes) -> None: ...
file_input_data = property(get_file_input_data, set_file_input_data)
```

## Default Value

""

## Remarks

When this property is set, the class will read in the data from this property instead of reading from the file contained in the [file_decompressed_name](#file_decompressed_name-property) property.

# z_compress_data property

(Decompression only) The LZC compressed file contents as a byte array.

## Syntax

```text
def set_z_compress_data(value: bytes) -> None: ...
z_compress_data = property(None, set_z_compress_data)
```

## Default Value

""

## Remarks

Normally you should set [archive_file](#archive_file-property) before invoking [extract](#extract-method). If you prefer to read the LZC compressed file from memory you may set z_compress_data instead. z_compress_data should be set to the entire contents of the LZC compressed file; this will allow you to read from the archive without writing any temporary files to disk.

If you would like to extract data from the archive without ever writing to disk you should also set [WriteToProgressEvent](#WriteToProgressEvent) to true, and you should set the value of [file_decompressed_name](#file_decompressed_name-property) to an empty string. Then, when you invoke [extract](#extract-method) the data will be provided in the [on_progress](#on_progress-event) event.

This property is write-only. Note that modifying a LZC compressed file stored in z_compress_data is not supported.

This property is write-only.

# abort method

Aborts the current operation.

## Syntax

```text
def abort() -> None: ...
```

## Remarks

abort may be used to immediately interrupt compression or decompression. Any files partially written by the class will be deleted.

# compress method

Creates the compressed archive.

## Syntax

```text
def compress() -> None: ...
```

## Remarks

Invoking compress creates the archive specified by [archive_file](#archive_file-property). When the method is called, the file specified by [file_decompressed_name](#file_decompressed_name-property) will be opened, and the file specified by [archive_file](#archive_file-property) will contain the compressed output.

# config method

Sets or retrieves a configuration setting.

## Syntax

```text
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](#zcompress-config-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](#zcompress-config-settings), you must call *Config("PROPERTY")*. The value will be returned as a string.

# extract method

Extracts the compressed file from the archive.

## Syntax

```text
def extract() -> None: ...
```

## Remarks

Invoking extract decompresses the archive specified by [archive_file](#archive_file-property). The compressed file will be extracted, and written to disk.

If [file_decompressed_name](#file_decompressed_name-property) is set to a nonempty string the file will be written there. Otherwise the class will automatically set [file_decompressed_name](#file_decompressed_name-property) to an appropriate value:

If [file_decompressed_name](#file_decompressed_name-property) is empty and [archive_file](#archive_file-property) ends in ".Z", this filename, less the ".Z" extension will be used. Otherwise the extension ".uncompressed" will be appended to the file name.

# reset method

Resets the class.

## Syntax

```text
def reset() -> None: ...
```

## Remarks

reset resets the state of the class. All properties will be set to their default values, and any files open will be closed.

# on_begin_file event

Fired before a file is processed.

## Syntax

```text
class ZCompressBeginFileEventParams(object):
  @property
  def index() -> int: ...

  @property
  def skip() -> bool: ...
  @skip.setter
  def skip(value) -> None: ...

# In class ZCompress:
@property
def on_begin_file() -> Callable[[ZCompressBeginFileEventParams], None]: ...
@on_begin_file.setter
def on_begin_file(event_hook: Callable[[ZCompressBeginFileEventParams], None]) -> None: ...
```

## Remarks

on_begin_file is fired before compression or decompression begins. *index* will contain 0.

You may use the *skip* parameter to tell the component to skip the file when compressing or decompressing.

# on_end_file event

Fired after a file is processed.

## Syntax

```text
class ZCompressEndFileEventParams(object):
  @property
  def index() -> int: ...

# In class ZCompress:
@property
def on_end_file() -> Callable[[ZCompressEndFileEventParams], None]: ...
@on_end_file.setter
def on_end_file(event_hook: Callable[[ZCompressEndFileEventParams], None]) -> None: ...
```

## Remarks

on_end_file is fired when compression or decompression finishes. *index* will contain 0.

# on_error event

Information about non-fatal errors.

## Syntax

```text
class ZCompressErrorEventParams(object):
  @property
  def description() -> str: ...

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

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

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

  @property
  def ignore() -> bool: ...
  @ignore.setter
  def ignore(value) -> None: ...

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

## Remarks

The on_error event is fired when non-fatal errors occur during compression or decompression. Note that if this event is fired during decompression this may indicate that the archive is corrupt.

By default these errors will cause the component to fail with an exception. The exception may be overridden by setting *ignore* to true. This will cause the error to be ignored, the file will be skipped if necessary, and the class will continue operation.

*error_code* will correspond to one of the following errors:

|  |  |
| --- | --- |
| 1 | Bad or missing CRC-32 checksum. |
| 2 | Failed to set creation date of a file. |
| 111 | Can't open file for read (skipping). |

*description* contains a textual description of the error. *index* and *file_name* contain the array index (where appropriate) and filename of the file being processed at the time of the error.

# on_overwrite event

Fired whenever a file exists and may be overwritten.

## Syntax

```text
class ZCompressOverwriteEventParams(object):
  @property
  def file_name() -> str: ...
  @file_name.setter
  def file_name(value) -> None: ...

  @property
  def overwrite() -> bool: ...
  @overwrite.setter
  def overwrite(value) -> None: ...

# In class ZCompress:
@property
def on_overwrite() -> Callable[[ZCompressOverwriteEventParams], None]: ...
@on_overwrite.setter
def on_overwrite(event_hook: Callable[[ZCompressOverwriteEventParams], None]) -> None: ...
```

## Remarks

on_overwrite is fired when a file is about to be overwritten, and would overwrite an existing file. The event is fired during decompression.

*file_name* contains the full name of the file, specified with its pathname.

*overwrite* specifies whether or not the file will be overwritten. For Zip, Jar, and Tar, this is equal by default to the value of the overwrite_files property. For Gzip, this value defaults to true.

Either of the parameters may be changed when the event is fired. Changing the value of *overwrite* will override the default behavior of the class, and cause the file to be overwritten or not overwritten, depending on the value set. If *file_name* is changed, the value of *overwrite* will be ignored, and the file will be written with the specified name. If a file of the new name also exists this file will be silently overwritten.

# on_progress event

Fired as progress is made.

## Syntax

```text
class ZCompressProgressEventParams(object):
  @property
  def data() -> bytes: ...

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

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

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

# In class ZCompress:
@property
def on_progress() -> Callable[[ZCompressProgressEventParams], None]: ...
@on_progress.setter
def on_progress(event_hook: Callable[[ZCompressProgressEventParams], None]) -> None: ...
```

## Remarks

The on_progress event is automatically fired as compression or decompression is performed. When [WriteToProgressEvent](#WriteToProgressEvent) is true, the output data is provided through the *data* parameter, allowing for it to be streamed out.

*file_name* contains the name of the file being written. If no file is being written, *file_name* will contain an empty string, and the output data will be provided exclusively through this event.

*bytes_processed* contains the total number of uncompressed bytes processed. *percent_processed* contains the percent of uncompressed bytes processed, corresponding roughly to the running time of the operation.

For **Gzip** extraction only, *bytes_processed* and *percent_processed* will reflect the number of compressed bytes extracted, as it is generally impossible to predetermine the total uncompressed size.

If [WriteToProgressEvent](#WriteToProgressEvent) is false, *data* will contain null.

# ZCompress 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](#config-method) method.

### ZCompress Config Settings

**WriteToProgressEvent**: Whether or not to write data to the Progress Event.If [WriteToProgressEvent](#WriteToProgressEvent) is set to true, then all data produced through invocations of [extract](#extract-method), extract_all, and [compress](#compress-method) will be written to the [on_progress](#on_progress-event) event as well as to disk. Applications may stream out the compressed or decompressed data by trapping this event and copying the data.

If [WriteToProgressEvent](#WriteToProgressEvent) is set to false, the data will not be streamed out, and the *Data* parameter of the [on_progress](#on_progress-event) event will contain null.

By default, this config is set to false.

### 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.

**MaskSensitiveData**: 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 *True*.

**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**: 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 configuration 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](platforms.md) section.

# ZCompress Errors

 **Errors**

The following errors may be generated by the class. Note that frequently the error message will contain more specific information than what is listed here.

Note that some non-fatal errors may be trapped and explicitly ignored in the [on_error](#on_error-event) event. This will allow the class to continue operation even in case of error.

### ZCompress Errors

|  |  |
| --- | --- |
| 111 | Can't open file for read. |
| 112 | Can't open file for write. |
| 113 | Can't create directory. |
| 114 | The file is too large. |
| 115 | Can't create empty archive. |
| 116 | The archive must be scanned prior to attempting this operation. |
| 117 | The array index is out of range. |
| 118 | The maximum size of the archive has been exceeded. |
| 119 | The archive must be specified, or streaming must be enabled. |
| 120 | The component is busy. |
| 124 | Must specify the compressed name. |
| 127 | Bad CRC-32 checksum. |
| 128 | Unable to set file date. |
| 133 | File already exists in the archive. |
| 150 | An I/O error has occurred (details follow). |