UnixCompress C++ Reference Documentation

CkUnixCompress

Current Version: 11.1.0

Requires Chilkat Bundle License

UNIX (.Z) compression component.

Object Creation

// Local variable on the stack
CkUnixCompress obj;

// Dynamically allocate/delete
CkUnixCompress *pObj = new CkUnixCompress();
// ...
delete pObj;

Properties

AbortCurrent

bool get_AbortCurrent(void);
void put_AbortCurrent(bool newVal);

Introduced in version 9.5.0.58

When set to true, causes the currently running method to abort. Methods that always finish quickly (i.e.have no length file operations or network communications) are not affected. If no method is running, then this property is automatically reset to false when the next method is called. When the abort occurs, this property is reset to false. Both synchronous and asynchronous method calls can be aborted. (A synchronous method call could be aborted by setting this property from a separate thread.)

DebugLogFilePath

void get_DebugLogFilePath(CkString &str);
const char *debugLogFilePath(void);
void put_DebugLogFilePath(const char *ansiOrUtf8Str);

If set to a file path, this property logs the LastErrorText of each Chilkat method or property call to the specified file. This logging helps identify the context and history of Chilkat calls leading up to any crash or hang, aiding in debugging.

Enabling the VerboseLogging property provides more detailed information. This property is mainly used for debugging rare instances where a Chilkat method call causes a hang or crash, which should generally not happen.

Possible causes of hangs include:

A timeout property set to 0, indicating an infinite timeout.
A hang occurring within an event callback in the application code.
An internal bug in the Chilkat code causing the hang.

More Information and Examples

Example showing how to use DebugLogFilePath.

HeartbeatMs

int get_HeartbeatMs(void);
void put_HeartbeatMs(int newVal);

The interval in milliseconds between each AbortCheck event callback, which enables an application to abort certain method calls before they complete. By default, HeartbeatMs is set to 0, meaning no AbortCheck event callbacks will trigger.

More Information and Examples

Event Callback Examples

LastErrorHtml

void get_LastErrorHtml(CkString &str);
const char *lastErrorHtml(void);

Provides HTML-formatted information about the last called method or property. If a method call fails or behaves unexpectedly, check this property for details. Note that information is available regardless of the method call's success.

LastErrorText

void get_LastErrorText(CkString &str);
const char *lastErrorText(void);

Provides plain text information about the last called method or property. If a method call fails or behaves unexpectedly, check this property for details. Note that information is available regardless of the method call's success.

More Information and Examples

Concept of LastErrorText LastErrorText Standard Information

LastErrorXml

void get_LastErrorXml(CkString &str);
const char *lastErrorXml(void);

Provides XML-formatted information about the last called method or property. If a method call fails or behaves unexpectedly, check this property for details. Note that information is available regardless of the method call's success.

LastMethodSuccess

bool get_LastMethodSuccess(void);
void put_LastMethodSuccess(bool newVal);

Indicates the success or failure of the most recent method call: true means success, false means failure. This property remains unchanged by property setters or getters. This method is present to address challenges in checking for null or Nothing returns in certain programming languages.

Utf8

bool get_Utf8(void);
void put_Utf8(bool newVal);

When set to true, all const char * arguments and return values are interpreted as UTF-8 strings. When set to false, they are interpreted as ANSI strings.

In Chilkat v11.0.0 and later, the default value is true. Before v11.0.0, it was false.

VerboseLogging

bool get_VerboseLogging(void);
void put_VerboseLogging(bool newVal);

If set to true, then the contents of LastErrorText (or LastErrorXml, or LastErrorHtml) may contain more verbose information. The default value is false. Verbose logging should only be used for debugging. The potentially large quantity of logged information may adversely affect peformance.

Version

void get_Version(CkString &str);
const char *version(void);

Version of the component/library, such as "10.1.0"

More Information and Examples

How to get the Chilkat version at runtime.

Methods

CompressFile

bool CompressFile(const char *inFilename, const char *destPath);

Compresses a file to create a UNIX compressed file (.Z). This compression uses the LZW (Lempel-Ziv-Welch) compression algorithm.

Returns true for success, false for failure.

CompressFileAsync ⁽¹⁾

CkTask *CompressFileAsync(const char *inFilename, const char *destPath);

Creates an asynchronous task to call the CompressFile method with the arguments provided.

Note: Async method event callbacks happen in the background thread. Accessing and updating UI elements existing in the main thread may require special considerations.

Note: The application is responsible for deleting (via the C++ delete operator) the object returned by this method.

Returns NULL on failure

CompressStringToFile

bool CompressStringToFile(const char *inStr, const char *charset, const char *destPath);

Unix compresses and creates a .Z file from string data. The charset specifies the character encoding used for the byte representation of the characters when compressed. The charset can be any one of a large number of character encodings, such as utf-8, iso-8859-1, Windows-1252, ucs-2, etc.

Returns true for success, false for failure.

More Information and Examples

List of Valid Charsets

LoadTaskCaller

bool LoadTaskCaller(CkTask &task);

Introduced in version 9.5.0.80

Loads the caller of the task's async method.

Returns true for success, false for failure.

UncompressFile

bool UncompressFile(const char *inFilename, const char *destPath);

Uncompresses a .Z file. (This compression uses the LZW (Lempel-Ziv-Welch) compression algorithm.)

Returns true for success, false for failure.

UncompressFileAsync ⁽¹⁾

CkTask *UncompressFileAsync(const char *inFilename, const char *destPath);

Creates an asynchronous task to call the UncompressFile method with the arguments provided.

Note: Async method event callbacks happen in the background thread. Accessing and updating UI elements existing in the main thread may require special considerations.

Note: The application is responsible for deleting (via the C++ delete operator) the object returned by this method.

Returns NULL on failure

UncompressFileToString

bool UncompressFileToString(const char *zFilename, const char *charset, CkString &outStr);
const char *uncompressFileToString(const char *zFilename, const char *charset);

Uncompresses a .Z file that contains a text file. The contents of the text file are returned as a string. The character encoding of the text file is specified by charset. Typical charsets are iso-8859-1, utf-8, windows-1252, shift_JIS, big5, etc.

Returns true for success, false for failure.

More Information and Examples

List of Valid Charsets

UncompressFileToStringAsync ⁽¹⁾

CkTask *UncompressFileToStringAsync(const char *zFilename, const char *charset);

Creates an asynchronous task to call the UncompressFileToString method with the arguments provided.

Note: Async method event callbacks happen in the background thread. Accessing and updating UI elements existing in the main thread may require special considerations.

Note: The application is responsible for deleting (via the C++ delete operator) the object returned by this method.

Returns NULL on failure

UnTarZ

bool UnTarZ(const char *zFilename, const char *destDir, bool bNoAbsolute);

Unpacks a .tar.Z file. The decompress and untar occur in streaming mode. There are no temporary files and the memory footprint is constant (and small) while untarring.

Returns true for success, false for failure.

UnTarZAsync ⁽¹⁾

CkTask *UnTarZAsync(const char *zFilename, const char *destDir, bool bNoAbsolute);

Creates an asynchronous task to call the UnTarZ method with the arguments provided.

Note: Async method event callbacks happen in the background thread. Accessing and updating UI elements existing in the main thread may require special considerations.

Note: The application is responsible for deleting (via the C++ delete operator) the object returned by this method.

Returns NULL on failure

Events

To implement an event callback, your application would define and implement a class that inherits from CkBaseProgress. Your application can implement methods to override some or all of the default/empty method implementations of the CkBaseProgress base class.

For example:

  CkUnixCompress unixcompress;

  MyUnixCompressProgress callbackObj;

  unixcompress.put_EventCallbackObject(&callbackObj);

MyUnixCompressProgress example:

#include "CkBaseProgress.h"

class MyUnixCompressProgress : public CkBaseProgress {

  public:
    MyUnixCompressProgress();
    virtual ~MyUnixCompressProgress();

    void AbortCheck(bool  *abort);

    void PercentDone(int pctDone, bool  *abort);

    void ProgressInfo(const char *name, const char *value);

    void TaskCompleted(CkTask &task);

};

AbortCheck

void AbortCheck(bool *abort);

Enables a method call to be aborted by triggering the AbortCheck event at intervals defined by the HeartbeatMs property. If HeartbeatMs is set to its default value of 0, no events will occur. For instance, set HeartbeatMs to 200 to trigger 5 AbortCheck events per second.

More Information and Examples

Chilkat Event Callback Examples

PercentDone

void PercentDone(int pctDone, bool *abort);

This provides the percentage completion for any method involving network communications or time-consuming processing, assuming the progress can be measured as a percentage. This event is triggered only when it's possible and logical to express the operation's progress as a percentage. The pctDone argument will range from 1 to 100. For methods that finish quickly, the number of PercentDone callbacks may vary, but the final callback will have pctDone equal to 100. For longer operations, callbacks will not exceed one per percentage point (e.g., 1, 2, 3, ..., 98, 99, 100).

The PercentDone callback also acts as an AbortCheck event. For fast methods where PercentDone fires, an AbortCheck event may not trigger since the PercentDone callback already provides an opportunity to abort. For longer operations, where time between PercentDone callbacks is extended, AbortCheck callbacks enable more responsive operation termination.

To abort the operation, set the abort output argument to true. This will cause the method to terminate and return a failure status or corresponding failure value.

More Information and Examples

Chilkat Event Callback Examples

ProgressInfo

void ProgressInfo(const char *name, const char *value);

This event callback provides tag name/value pairs that detail what occurs during a method call. To discover existing tag names, create code to handle the event, emit the pairs, and review them. Most tag names are self-explanatory.

More Information and Examples

Chilkat Event Callback Examples

TaskCompleted

void TaskCompleted(CkTask &task);

Called from the background thread when an asynchronous task completes.

Deprecated

CompressFileToMem Deprecated

bool CompressFileToMem(const char *inFilename, CkByteData &outData);

Unix compresses a file to an in-memory image of a .Z file. (This compression uses the LZW (Lempel-Ziv-Welch) compression algorithm.)

Returns true for success, false for failure.

CompressFileToMemAsync Deprecated ⁽¹⁾

CkTask *CompressFileToMemAsync(const char *inFilename);

Creates an asynchronous task to call the CompressFileToMem method with the arguments provided.

Note: Async method event callbacks happen in the background thread. Accessing and updating UI elements existing in the main thread may require special considerations.

Note: The application is responsible for deleting (via the C++ delete operator) the object returned by this method.

Returns NULL on failure

CompressMemory Deprecated

bool CompressMemory(CkByteData &inData, CkByteData &outData);

Compresses in-memory data to an in-memory image of a .Z file. (This compression uses the LZW (Lempel-Ziv-Welch) compression algorithm.)

Returns true for success, false for failure.

CompressMemToFile Deprecated

bool CompressMemToFile(CkByteData &inData, const char *destPath);

Unix compresses and creates a .Z file from in-memory data. (This compression uses the LZW (Lempel-Ziv-Welch) compression algorithm.)

Returns true for success, false for failure.

CompressString Deprecated

bool CompressString(const char *inStr, const char *charset, CkByteData &outBytes);

Compresses a string to an in-memory image of a .Z file. Prior to compression, the string is converted to the character encoding specified by charset. The charset can be any one of a large number of character encodings, such as utf-8, iso-8859-1, Windows-1252, ucs-2, etc.

Returns true for success, false for failure.

More Information and Examples

List of Valid Charsets

UncompressFileToMem Deprecated

bool UncompressFileToMem(const char *inFilename, CkByteData &outData);

Uncompresses a .Z file directly to memory. (This compression uses the LZW (Lempel-Ziv-Welch) compression algorithm.)

Returns true for success, false for failure.

UncompressFileToMemAsync Deprecated ⁽¹⁾

CkTask *UncompressFileToMemAsync(const char *inFilename);

Creates an asynchronous task to call the UncompressFileToMem method with the arguments provided.

Note: Async method event callbacks happen in the background thread. Accessing and updating UI elements existing in the main thread may require special considerations.

Note: The application is responsible for deleting (via the C++ delete operator) the object returned by this method.

Returns NULL on failure

UncompressMemory Deprecated

bool UncompressMemory(CkByteData &inData, CkByteData &outData);

Uncompresses from an in-memory image of a .Z file directly into memory. (This compression uses the LZW (Lempel-Ziv-Welch) compression algorithm.)

Returns true for success, false for failure.

UncompressMemToFile Deprecated

bool UncompressMemToFile(CkByteData &inData, const char *destPath);

Uncompresses from an in-memory image of a .Z file to a file. (This compression uses the LZW (Lempel-Ziv-Welch) compression algorithm.)

Returns true for success, false for failure.

UncompressString Deprecated

bool UncompressString(CkByteData &inCompressedData, const char *charset, CkString &outStr);
const char *uncompressString(CkByteData &inCompressedData, const char *charset);

Uncompresses from an in-memory image of a .Z file directly to a string. The charset specifies the character encoding used to interpret the bytes resulting from the decompression. The charset can be any one of a large number of character encodings, such as utf-8, iso-8859-1, Windows-1252, ucs-2, etc.

Returns true for success, false for failure.

More Information and Examples

List of Valid Charsets