UnixCompress C Reference Documentation
UnixCompress
Current Version: 10.1.2
UNIX (.Z) compression component.
Create/Dispose
HCkUnixCompress instance = CkUnixCompress_Create(); // ... CkUnixCompress_Dispose(instance);
Creates an instance of the HCkUnixCompress object and returns a handle ("void *" pointer). The handle is passed in the 1st argument for the functions listed on this page.
Objects created by calling CkUnixCompress_Create must be freed by calling this method. A memory leak occurs if a handle is not disposed by calling this function. Also, any handle returned by a Chilkat "C" function must also be freed by the application by calling the appropriate Dispose method, such as CkUnixCompress_Dispose.
Callback Functions
Provides the opportunity for a method call to be aborted. If TRUE is returned, the operation in progress is aborted. Return FALSE to allow the current method call to continue. This callback function is called periodically based on the value of the HeartbeatMs property. (If HeartbeatMs is 0, then no callbacks are made.) As an example, to make 5 AbortCheck callbacks per second, set the HeartbeatMs property equal to 200.
See Also:C Example using Callback Functions
Provides the percentage completed for any method that involves network communications or time-consuming processing (assuming it is a method where a percentage completion can be measured). This callback is only called when it is possible to know a percentage completion, and when it makes sense to express the operation as a percentage completed. The pctDone argument will have a value from 1 to 100. For methods that complete very quickly, the number of PercentDone callbacks will vary, but the final callback should have a value of 100. For long running operations, no more than one callback per percentage point will occur (for example: 1, 2, 3, ... 98, 99, 100).
This callback counts as an AbortCheck callback, and takes the place of the AbortCheck event when it fires.
The return value indicates whether the method call should be aborted, or whether it should proceed. Return TRUE to abort, and FALSE to proceed.
This is a general callback that provides name/value information about what is happening at certain points during a method call. To see the information provided in ProgressInfo callbacks, if any, write code to handle this event and log the name/value pairs. Most are self-explanatory.
Called in the background thread when an asynchronous task completes. (Note: When an async method is running, all callbacks are in the background thread.)
Properties
AbortCurrent
void CkUnixCompress_putAbortCurrent(HCkUnixCompress cHandle, BOOL newVal);
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.)
topDebugLogFilePath
void CkUnixCompress_putDebugLogFilePath(HCkUnixCompress cHandle, const char *newVal);
const char *CkUnixCompress_debugLogFilePath(HCkUnixCompress cHandle);
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.
HeartbeatMs
void CkUnixCompress_putHeartbeatMs(HCkUnixCompress cHandle, int newVal);
The number of milliseconds between each AbortCheck event callback. The AbortCheck callback allows an application to abort any method call prior to completion. If HeartbeatMs is 0 (the default), no AbortCheck event callbacks will fire.
topLastErrorHtml
const char *CkUnixCompress_lastErrorHtml(HCkUnixCompress cHandle);
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.
topLastErrorText
const char *CkUnixCompress_lastErrorText(HCkUnixCompress cHandle);
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.
LastErrorXml
const char *CkUnixCompress_lastErrorXml(HCkUnixCompress cHandle);
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.
topLastMethodSuccess
void CkUnixCompress_putLastMethodSuccess(HCkUnixCompress cHandle, 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.
topUtf8
void CkUnixCompress_putUtf8(HCkUnixCompress cHandle, BOOL newVal);
When set to TRUE, all "const char *" arguments are interpreted as utf-8 strings. If set to FALSE (the default), then "const char *" arguments are interpreted as ANSI strings. Also, when set to TRUE, and Chilkat method returning a "const char *" is returning the utf-8 representation. If set to FALSE, all "const char *" return values are ANSI strings.
topVerboseLogging
void CkUnixCompress_putVerboseLogging(HCkUnixCompress cHandle, 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.
topVersion
const char *CkUnixCompress_version(HCkUnixCompress cHandle);
Methods
CompressFile
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.
topCompressFileAsync (1)
Creates an asynchronous task to call the CompressFile method with the arguments provided.
Returns NULL on failure
topCompressFileToMem
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.
topCompressFileToMemAsync (1)
Creates an asynchronous task to call the CompressFileToMem method with the arguments provided.
Returns NULL on failure
topCompressMemory
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.
topCompressMemToFile
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.
topCompressString
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.
CompressStringToFile
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.
LoadTaskCaller
UncompressFile
Uncompresses a .Z file. (This compression uses the LZW (Lempel-Ziv-Welch) compression algorithm.)
Returns TRUE for success, FALSE for failure.
topUncompressFileAsync (1)
Creates an asynchronous task to call the UncompressFile method with the arguments provided.
Returns NULL on failure
topUncompressFileToMem
Uncompresses a .Z file directly to memory. (This compression uses the LZW (Lempel-Ziv-Welch) compression algorithm.)
Returns TRUE for success, FALSE for failure.
topUncompressFileToMemAsync (1)
Creates an asynchronous task to call the UncompressFileToMem method with the arguments provided.
Returns NULL on failure
topUncompressFileToString
const char *CkUnixCompress_uncompressFileToString(HCkUnixCompress cHandle, 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.
UncompressFileToStringAsync (1)
Creates an asynchronous task to call the UncompressFileToString method with the arguments provided.
Returns NULL on failure
topUncompressMemory
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.
topUncompressMemToFile
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.
topUncompressString
const char *CkUnixCompress_uncompressString(HCkUnixCompress cHandle, HCkByteData 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.
UnTarZ
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.
topUnTarZAsync (1)
Creates an asynchronous task to call the UnTarZ method with the arguments provided.
Returns NULL on failure
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