Compression Tcl Reference Documentation
Compression
Current Version: 11.0.0
Implements the Bzip2, Deflate, and LZW compression algorithms.
Object Creation
set myCompression [new CkCompression]
Properties
Algorithm
# ckStr is a CkString
CkCompression_get_Algorithm $myCompression $ckStr
set strVal [CkCompression_get_algorithm $myCompression]
CkCompression_put_Algorithm $myCompression $strVal
Specifies the compression algorithm: "deflate", "zlib", "bzip2", or "lzw". Note that "ppmd" is deprecated and should not be used. It was only available for 32-bit systems and specifically used the "J" variant. Please transition to one of the recommended algorithms.
topCharset
# ckStr is a CkString
CkCompression_get_Charset $myCompression $ckStr
set strVal [CkCompression_get_charset $myCompression]
CkCompression_put_Charset $myCompression $strVal
Specifies the character encoding for compressing or decompressing strings. Options include utf-8 (default), windows-1252, Shift_JIS, iso-8859-2, and others.
DebugLogFilePath
# ckStr is a CkString
CkCompression_get_DebugLogFilePath $myCompression $ckStr
set strVal [CkCompression_get_debugLogFilePath $myCompression]
CkCompression_put_DebugLogFilePath $myCompression $strVal
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.
DeflateLevel
set intVal [CkCompression_get_DeflateLevel $myCompression]
CkCompression_put_DeflateLevel $myCompression $intVal
This property allows for customization of the compression level for the "deflate" and "zlib" compression algoirthms. ("zlib" is just the deflate algorithm with a zlib header.) A value of 0 = no compression, while 9 = maximum compression. The default is 6.
topEncodingMode
# ckStr is a CkString
CkCompression_get_EncodingMode $myCompression $ckStr
set strVal [CkCompression_get_encodingMode $myCompression]
CkCompression_put_EncodingMode $myCompression $strVal
Controls the encoding expected by methods ending in "ENC", such as CompressBytesENC. Valid values are "base64", "hex", "url", and "quoted-printable". Compression methods ending in ENC return the binary compressed data as an encoded string using this encoding. Decompress methods expect the input string to be this encoding.
topFirstChunk
set boolVal [CkCompression_get_FirstChunk $myCompression]
CkCompression_put_FirstChunk $myCompression $boolVal
This property applies to FirstChunk and LastChunk aware compression and decompression methods. It signifies that the data being compressed is the first of multiple chunks.
The default value is 1.
When both FirstChunk and LastChunk, it means the entire amount of data to be compressed or decompressed is presented in a single call.
LastChunk
set boolVal [CkCompression_get_LastChunk $myCompression]
CkCompression_put_LastChunk $myCompression $boolVal
This property applies to FirstChunk and LastChunk aware compression and decompression methods. It signifies that the data being compressed is the last of multiple chunks.
The default value is 1.
When both FirstChunk and LastChunk, it means the entire amount of data to be compressed or decompressed is presented in a single call.
LastErrorHtml
# ckStr is a CkString
CkCompression_get_LastErrorHtml $myCompression $ckStr
set strVal [CkCompression_get_lastErrorHtml $myCompression]
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
# ckStr is a CkString
CkCompression_get_LastErrorText $myCompression $ckStr
set strVal [CkCompression_get_lastErrorText $myCompression]
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
# ckStr is a CkString
CkCompression_get_LastErrorXml $myCompression $ckStr
set strVal [CkCompression_get_lastErrorXml $myCompression]
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
set boolVal [CkCompression_get_LastMethodSuccess $myCompression]
CkCompression_put_LastMethodSuccess $myCompression $boolVal
Indicates the success or failure of the most recent method call: 1 means success, 0 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.
UncommonOptions
# ckStr is a CkString
CkCompression_get_UncommonOptions $myCompression $ckStr
set strVal [CkCompression_get_uncommonOptions $myCompression]
CkCompression_put_UncommonOptions $myCompression $strVal
This is a catch-all property to be used for uncommon needs. This property defaults to the empty string and should typically remain empty.
Can be set to a list of the following comma separated keywords:
Crypt2CompressHdr- Duplicates the compression and decompression as implemented in the deprecated and removed Crypt2 compression functions.
VerboseLogging
set boolVal [CkCompression_get_VerboseLogging $myCompression]
CkCompression_put_VerboseLogging $myCompression $boolVal
If set to 1, then the contents of LastErrorText (or LastErrorXml, or LastErrorHtml) may contain more verbose information. The default value is 0. Verbose logging should only be used for debugging. The potentially large quantity of logged information may adversely affect peformance.
Version
# ckStr is a CkString
CkCompression_get_Version $myCompression $ckStr
set strVal [CkCompression_get_version $myCompression]
Methods
CompressBd
Compresses the data contained in bd. This method is not FirstChunk/LastChunk aware.
Returns 1 for success, 0 for failure.
CompressBdAsync (1)
Creates an asynchronous task to call the CompressBd method with the arguments provided.
Returns NULL on failure
CompressBd2
This method compresses the data in bdIn without modifying it and appends the compressed data to bdOut. It is also FirstChunk/LastChunk aware.
Returns 1 for success, 0 for failure.
topCompressBd2Async (1)
# bdIn is a CkBinData
# bdOut is a CkBinData
set ret_task [CkCompression_CompressBd2Async $bdIn $bdOut]
Creates an asynchronous task to call the CompressBd2 method with the arguments provided.
Returns NULL on failure
CompressBytes Deprecated
# outData is a CkByteData (output)
set status [CkCompression_CompressBytes $data $outData]
Compresses byte data.
This method is FirstChunk/LastChunk aware.
Returns 1 for success, 0 for failure.
CompressBytesAsync Deprecated (1)
Creates an asynchronous task to call the CompressBytes method with the arguments provided.
Returns NULL on failure
CompressEncryptFile
# srcPath is a string
# destPath is a string
set status [CkCompression_CompressEncryptFile $cryptParams $srcPath $destPath]
Performs file-to-file compression and encryption. Files of any size may be compressed because the file is compressed and encrypted internally in streaming mode.
Returns 1 for success, 0 for failure.
CompressEncryptFileAsync (1)
# cryptParams is a CkJsonObject
# srcPath is a string
# destPath is a string
set ret_task [CkCompression_CompressEncryptFileAsync $cryptParams $srcPath $destPath]
Creates an asynchronous task to call the CompressEncryptFile method with the arguments provided.
Returns NULL on failure
CompressFile
# destPath is a string
set status [CkCompression_CompressFile $srcPath $destPath]
Performs file-to-file compression. Files of any size may be compressed because the file is compressed internally in streaming mode.
Returns 1 for success, 0 for failure.
CompressFileAsync (1)
# srcPath is a string
# destPath is a string
set ret_task [CkCompression_CompressFileAsync $srcPath $destPath]
Creates an asynchronous task to call the CompressFile method with the arguments provided.
Returns NULL on failure
CompressSb
# binData is a CkBinData
set status [CkCompression_CompressSb $sb $binData]
Compresses the contents of sb and appends the compressed bytes to binData.
This method is FirstChunk/LastChunk aware.
Returns 1 for success, 0 for failure.
topCompressSbAsync (1)
# sb is a CkStringBuilder
# binData is a CkBinData
set ret_task [CkCompression_CompressSbAsync $sb $binData]
Creates an asynchronous task to call the CompressSb method with the arguments provided.
Returns NULL on failure
CompressStr Deprecated
Compresses a string and appends to bd. The byte representation (character encoding) of the actual bytes to be compressed is determined by the Charset property. This method is FirstChunk / LastChunk aware.
Returns 1 for success, 0 for failure.
topCompressStrAsync Deprecated (1)
# str is a string
# bd is a CkBinData
set ret_task [CkCompression_CompressStrAsync $str $bd]
Creates an asynchronous task to call the CompressStr method with the arguments provided.
Returns NULL on failure
CompressStream
Compresses a stream. Internally, the strm's source is read, compressed, and the compressed data written to the strm's sink. It does this in streaming fashion. Extremely large or even infinite streams can be compressed with stable ungrowing memory usage.
Returns 1 for success, 0 for failure.
CompressStreamAsync (1)
Creates an asynchronous task to call the CompressStream method with the arguments provided.
Returns NULL on failure
CompressString Deprecated
# outData is a CkByteData (output)
set status [CkCompression_CompressString $str $outData]
Compresses a string.
This method is FirstChunk/LastChunk aware.
Returns 1 for success, 0 for failure.
CompressStringAsync Deprecated (1)
Creates an asynchronous task to call the CompressString method with the arguments provided.
Returns NULL on failure
CompressStringENC
# outStr is a CkString (output)
set status [CkCompression_CompressStringENC $str $outStr]
set retStr [CkCompression_compressStringENC $myCompression $str]
Compresses a string and returns the compressed data encoded to a string. The output encoding (hex, base64, etc.) is determined by the EncodingMode property setting.
Returns 1 for success, 0 for failure.
CompressStringENCAsync (1)
Creates an asynchronous task to call the CompressStringENC method with the arguments provided.
Returns NULL on failure
DecompressBd
Decompresses the data contained in bd. This method is not FirstChunk/LastChunk aware.
Returns 1 for success, 0 for failure.
DecompressBdAsync (1)
Creates an asynchronous task to call the DecompressBd method with the arguments provided.
Returns NULL on failure
DecompressBd2
This method decompresses the data in bdIn without modifying it and appends the decompressed data to bdOut. It is also FirstChunk/LastChunk aware.
Returns 1 for success, 0 for failure.
topDecompressBd2Async (1)
# bdIn is a CkBinData
# bdOut is a CkBinData
set ret_task [CkCompression_DecompressBd2Async $bdIn $bdOut]
Creates an asynchronous task to call the DecompressBd2 method with the arguments provided.
Returns NULL on failure
DecompressBytes Deprecated
# outData is a CkByteData (output)
set status [CkCompression_DecompressBytes $data $outData]
This method decompresses bytes.
This method is FirstChunk/LastChunk aware.
Returns 1 for success, 0 for failure.
DecompressBytesAsync Deprecated (1)
Creates an asynchronous task to call the DecompressBytes method with the arguments provided.
Returns NULL on failure
DecompressFile
# destPath is a string
set status [CkCompression_DecompressFile $srcPath $destPath]
Performs file-to-file decompression (the opposite of CompressFile). Internally the file is decompressed in streaming mode which allows files of any size to be decompressed.
Returns 1 for success, 0 for failure.
DecompressFileAsync (1)
# srcPath is a string
# destPath is a string
set ret_task [CkCompression_DecompressFileAsync $srcPath $destPath]
Creates an asynchronous task to call the DecompressFile method with the arguments provided.
Returns NULL on failure
DecompressSb
# sb is a CkStringBuilder
set status [CkCompression_DecompressSb $binData $sb]
Decompresses the contents of binData and appends the decompressed string to sb.
This method is FirstChunk/LastChunk aware.
Returns 1 for success, 0 for failure.
topDecompressSbAsync (1)
# binData is a CkBinData
# sb is a CkStringBuilder
set ret_task [CkCompression_DecompressSbAsync $binData $sb]
Creates an asynchronous task to call the DecompressSb method with the arguments provided.
Returns NULL on failure
DecompressStream
Decompresses a stream. Internally, the strm's source is read, decompressed, and the decompressed data written to the strm's sink. It does this in streaming fashion. Extremely large or even infinite streams can be decompressed with stable ungrowing memory usage.
Returns 1 for success, 0 for failure.
DecompressStreamAsync (1)
Creates an asynchronous task to call the DecompressStream method with the arguments provided.
Returns NULL on failure
DecryptDecompressFile
# srcPath is a string
# destPath is a string
set status [CkCompression_DecryptDecompressFile $cryptParams $srcPath $destPath]
Performs file-to-file decryption and decompression.
Returns 1 for success, 0 for failure.
DecryptDecompressFileAsync (1)
# cryptParams is a CkJsonObject
# srcPath is a string
# destPath is a string
set ret_task [CkCompression_DecryptDecompressFileAsync $cryptParams $srcPath $destPath]
Creates an asynchronous task to call the DecryptDecompressFile method with the arguments provided.
Returns NULL on failure
LoadTaskCaller
Deprecated
BeginCompressBytes
# outData is a CkByteData (output)
set status [CkCompression_BeginCompressBytes $data $outData]
Large amounts of binary byte data may be compressed in chunks by first calling BeginCompressBytes, followed by 0 or more calls to MoreCompressedBytes, and ending with a final call to EndCompressBytes. Each call returns 0 or more bytes of compressed data which may be output to a compressed data stream (such as a file, socket, etc.).
Returns 1 for success, 0 for failure.
BeginCompressBytesENC
# outStr is a CkString (output)
set status [CkCompression_BeginCompressBytesENC $data $outStr]
set retStr [CkCompression_beginCompressBytesENC $myCompression $data]
Large amounts of binary byte data may be compressed in chunks by first calling BeginCompressBytesENC, followed by 0 or more calls to MoreCompressedBytesENC, and ending with a final call to EndCompressBytesENC. Each call returns 0 or more characters of compressed data (encoded as a string according to the EncodingMode property setting) which may be output to a compressed data stream (such as a file, socket, etc.).
Returns 1 for success, 0 for failure.
topBeginCompressString
# outData is a CkByteData (output)
set status [CkCompression_BeginCompressString $str $outData]
Large amounts of string data may be compressed in chunks by first calling BeginCompressString, followed by 0 or more calls to MoreCompressedString, and ending with a final call to EndCompressString. Each call returns 0 or more bytes of compressed data which may be output to a compressed data stream (such as a file, socket, etc.).
Returns 1 for success, 0 for failure.
BeginCompressStringENC
# outStr is a CkString (output)
set status [CkCompression_BeginCompressStringENC $str $outStr]
set retStr [CkCompression_beginCompressStringENC $myCompression $str]
Large amounts of string data may be compressed in chunks by first calling BeginCompressStringENC, followed by 0 or more calls to MoreCompressedStringENC, and ending with a final call to EndCompressStringENC. Each call returns 0 or more characters of compressed data (encoded as a string according to the EncodingMode property setting) which may be output to a compressed data stream (such as a file, socket, etc.).
Returns 1 for success, 0 for failure.
BeginDecompressBytes
# outData is a CkByteData (output)
set status [CkCompression_BeginDecompressBytes $data $outData]
A compressed data stream may be decompressed in chunks by first calling BeginDecompressBytes, followed by 0 or more calls to MoreDecompressedBytes, and ending with a final call to EndDecompressBytes. Each call returns 0 or more bytes of decompressed data.
Returns 1 for success, 0 for failure.
BeginDecompressBytesENC
# outData is a CkByteData (output)
set status [CkCompression_BeginDecompressBytesENC $str $outData]
The input to this method is an encoded string containing compressed data. The EncodingMode property should be set prior to calling this method. The input string is decoded according to the EncodingMode (hex, base64, etc.) and then decompressed.
A compressed data stream may be decompressed in chunks by first calling BeginDecompressBytesENC, followed by 0 or more calls to MoreDecompressedBytesENC, and ending with a final call to EndDecompressBytesENC. Each call returns 0 or more bytes of decompressed data.
Returns 1 for success, 0 for failure.
topBeginDecompressString
# outStr is a CkString (output)
set status [CkCompression_BeginDecompressString $data $outStr]
set retStr [CkCompression_beginDecompressString $myCompression $data]
A compressed data stream may be decompressed in chunks by first calling BeginDecompressString, followed by 0 or more calls to MoreDecompressedString, and ending with a final call to EndDecompressString. Each call returns 0 or more characters of decompressed text.
Returns 1 for success, 0 for failure.
BeginDecompressStringENC
# outStr is a CkString (output)
set status [CkCompression_BeginDecompressStringENC $str $outStr]
set retStr [CkCompression_beginDecompressStringENC $myCompression $str]
The input to this method is an encoded string containing compressed data. The EncodingMode property should be set prior to calling this method. The input string is decoded according to the EncodingMode (hex, base64, etc.) and then decompressed.
A compressed data stream may be decompressed in chunks by first calling BeginDecompressStringENC, followed by 0 or more calls to MoreDecompressedStringENC, and ending with a final call to EndDecompressStringENC. Each call returns 0 or more characters of decompressed text.
Returns 1 for success, 0 for failure.
topEndCompressBytes
Must be callled to finalize a compression stream. Returns any remaining (buffered) compressed data.
(See BeginCompressBytes)
Returns 1 for success, 0 for failure.
EndCompressBytesENC
set status [CkCompression_EndCompressBytesENC $outStr]
set retStr [CkCompression_endCompressBytesENC $myCompression]
Must be callled to finalize a compression stream. Returns any remaining (buffered) compressed data.
(See BeginCompressBytesENC)
Returns 1 for success, 0 for failure.
topEndCompressString
Must be callled to finalize a compression stream. Returns any remaining (buffered) compressed data.
(See BeginCompressString)
Returns 1 for success, 0 for failure.
EndCompressStringENC
set status [CkCompression_EndCompressStringENC $outStr]
set retStr [CkCompression_endCompressStringENC $myCompression]
Must be callled to finalize a compression stream. Returns any remaining (buffered) compressed data.
(See BeginCompressStringENC)
Returns 1 for success, 0 for failure.
EndDecompressBytes
Called to finalize the decompression stream and return any remaining (buffered) decompressed data.
(See BeginDecompressBytes)
Returns 1 for success, 0 for failure.
EndDecompressBytesENC
Called to finalize the decompression stream and return any remaining (buffered) decompressed data.
The input to this method is an encoded string containing compressed data. The EncodingMode property should be set prior to calling this method. The input string is decoded according to the EncodingMode (hex, base64, etc.) and then decompressed.
(See BeginDecompressBytesENC)
Returns 1 for success, 0 for failure.
topEndDecompressString
set status [CkCompression_EndDecompressString $outStr]
set retStr [CkCompression_endDecompressString $myCompression]
Called to finalize the decompression stream and return any remaining (buffered) decompressed data.
(See BeginDecompressString)
Returns 1 for success, 0 for failure.
EndDecompressStringENC
set status [CkCompression_EndDecompressStringENC $outStr]
set retStr [CkCompression_endDecompressStringENC $myCompression]
Called to finalize the decompression stream and return any remaining (buffered) decompressed data.
The input to this method is an encoded string containing compressed data. The EncodingMode property should be set prior to calling this method. The input string is decoded according to the EncodingMode (hex, base64, etc.) and then decompressed.
(See BeginDecompressStringENC)
Returns 1 for success, 0 for failure.
topMoreCompressBytes
# outData is a CkByteData (output)
set status [CkCompression_MoreCompressBytes $data $outData]
MoreCompressBytesENC
# outStr is a CkString (output)
set status [CkCompression_MoreCompressBytesENC $data $outStr]
set retStr [CkCompression_moreCompressBytesENC $myCompression $data]
MoreCompressString
# outData is a CkByteData (output)
set status [CkCompression_MoreCompressString $str $outData]
MoreCompressStringENC
# outStr is a CkString (output)
set status [CkCompression_MoreCompressStringENC $str $outStr]
set retStr [CkCompression_moreCompressStringENC $myCompression $str]
MoreDecompressBytes
# outData is a CkByteData (output)
set status [CkCompression_MoreDecompressBytes $data $outData]
MoreDecompressBytesENC
# outData is a CkByteData (output)
set status [CkCompression_MoreDecompressBytesENC $str $outData]
The input to this method is an encoded string containing compressed data. The EncodingMode property should be set prior to calling this method. The input string is decoded according to the EncodingMode (hex, base64, etc.) and then decompressed.
(See BeginDecompressBytesENC)
Returns 1 for success, 0 for failure.
topMoreDecompressString
# outStr is a CkString (output)
set status [CkCompression_MoreDecompressString $data $outStr]
set retStr [CkCompression_moreDecompressString $myCompression $data]
MoreDecompressStringENC
# outStr is a CkString (output)
set status [CkCompression_MoreDecompressStringENC $str $outStr]
set retStr [CkCompression_moreDecompressStringENC $myCompression $str]
The input to this method is an encoded string containing compressed data. The EncodingMode property should be set prior to calling this method. The input string is decoded according to the EncodingMode (hex, base64, etc.) and then decompressed.
(See BeginDecompressStringENC)
Returns 1 for success, 0 for failure.
top