UnixCompress Classic ASP Reference Documentation

UnixCompress

Current Version: 11.6.0

Chilkat.UnixCompress

Compress, uncompress, and unpack legacy UNIX .Z files.

Chilkat.UnixCompress provides UNIX compress and uncompress functionality for legacy .Z files. It supports file-based, memory-based, and string-based workflows, uses LZW compression, can unpack .tar.Z archives, and includes abort and progress-related support for longer-running operations.

Compress to .Z

Compress files, memory data, or strings into UNIX .Z format using LZW compression.

Uncompress .Z data

Expand UNIX-compressed data back to files, memory, byte arrays, or text depending on the application workflow.

File workflows

Compress and uncompress directly between input and output files when working with existing filesystem data.

Memory workflows

Work with compressed or uncompressed byte data in memory when temporary files are not desired.

String workflows

Compress and uncompress text using an explicit character set so string data round-trips correctly.

Unpack tar.Z archives

Use UnTarZ to decompress and extract legacy .tar.Z archives in a single workflow.

Common pattern: Use UnixCompress when the data is in classic UNIX .Z format or when a .tar.Z archive must be unpacked. Use Chilkat.Gzip for .gz and .tar.gz files, Chilkat.Bz2 for .bz2 files, and Chilkat.Compression for raw compression algorithms and general-purpose compression workflows.

Object Creation

set unixCompress = Server.CreateObject("Chilkat.UnixCompress")

' ... use unixCompress ...

set unixCompress = Nothing

Classic ASP creates Chilkat objects with Server.CreateObject. The registered Chilkat ActiveX must match the bitness of the IIS application pool: a pool with Enable 32-Bit Applications set to True needs the 32-bit ActiveX, otherwise the 64-bit ActiveX. To bind to a specific major version of Chilkat, append the major version number to the ProgID, such as Server.CreateObject("Chilkat.UnixCompress.11") for Chilkat v11.*.*.

VBScript requires set when assigning an object, so the signatures on this page show set x = obj.Method(...) for methods that return a Chilkat object; test the result with Is Nothing, since a method that fails to return an object returns Nothing. A method with no return value is called as a statement without parentheses (obj.Method arg1, arg2). Boolean properties, arguments and return values are integers in the ActiveX: pass 1 or 0, and test success with = 1. Byte arrays are Variant arrays and can be sent with Response.BinaryWrite. Asynchronous (*Async) methods and event callbacks are not used from Classic ASP.

Properties

AbortCurrent
unixCompress.AbortCurrent ' Long
Introduced in version 9.5.0.58

When set to 1, 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 0 when the next method is called. When the abort occurs, this property is reset to 0. Both synchronous and asynchronous method calls can be aborted. (A synchronous method call could be aborted by setting this property from a separate thread.)

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DebugLogFilePath
unixCompress.DebugLogFilePath ' String

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.

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LastBinaryResult
unixCompress.LastBinaryResult ' Variant (read-only)

This property is mainly used in SQL Server stored procedures to retrieve binary data from the last method call that returned binary data. It is only accessible if Chilkat.Global.KeepBinaryResult is set to 1. This feature allows for the retrieval of large varbinary results in an SQL Server environment, which has restrictions on returning large data via method calls, though temp tables can handle binary properties.

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LastErrorHtml
unixCompress.LastErrorHtml ' String (read-only)

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.

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LastErrorText
unixCompress.LastErrorText ' String (read-only)

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.

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LastErrorXml
unixCompress.LastErrorXml ' String (read-only)

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.

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LastMethodSuccess
unixCompress.LastMethodSuccess ' Long

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. Note: This property does not apply to methods that return integer values or to boolean-returning methods where the boolean does not indicate success or failure.

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LastStringResult
unixCompress.LastStringResult ' String (read-only)

In SQL Server stored procedures, this property holds the string return value of the most recent method call that returns a string. It is accessible only when Chilkat.Global.KeepStringResult is set to TRUE. SQL Server has limitations on string lengths returned from methods and properties, but temp tables can be used to access large strings.

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LastStringResultLen
unixCompress.LastStringResultLen ' Long (read-only)

The length, in characters, of the string contained in the LastStringResult property.

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VerboseLogging
unixCompress.VerboseLogging ' Long

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.

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Version
unixCompress.Version ' String (read-only)

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

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Methods

CompressFile
success = unixCompress.CompressFile(inFilename, destPath) ' Long (1/0)

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

Returns 1 for success, 0 for failure.

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CompressFileToMem
bytes = unixCompress.CompressFileToMem(inFilename) ' Variant

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

Returns a zero-length byte array (as a Variant) on failure.
An empty array will have a UBound of -1 meaning 0 elements.

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CompressMemory
bytes = unixCompress.CompressMemory(inData) ' Variant

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

Returns a zero-length byte array (as a Variant) on failure.
An empty array will have a UBound of -1 meaning 0 elements.

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CompressMemToFile
success = unixCompress.CompressMemToFile(inData, destPath) ' Long (1/0)

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

Returns 1 for success, 0 for failure.

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CompressString
bytes = unixCompress.CompressString(inStr, charset) ' Variant

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 a zero-length byte array (as a Variant) on failure.
An empty array will have a UBound of -1 meaning 0 elements.

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CompressStringToFile
success = unixCompress.CompressStringToFile(inStr, charset, destPath) ' Long (1/0)

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 1 for success, 0 for failure.

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ReadFile
bytes = unixCompress.ReadFile(filename) ' Variant

Convenience method to read an entire file and return as a byte array.

Returns a zero-length byte array (as a Variant) on failure.
An empty array will have a UBound of -1 meaning 0 elements.

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UncompressFile
success = unixCompress.UncompressFile(inFilename, destPath) ' Long (1/0)

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

Returns 1 for success, 0 for failure.

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UncompressFileToMem
bytes = unixCompress.UncompressFileToMem(inFilename) ' Variant

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

Returns a zero-length byte array (as a Variant) on failure.
An empty array will have a UBound of -1 meaning 0 elements.

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UncompressFileToString
str = unixCompress.UncompressFileToString(zFilename, charset) ' String

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 Nothing on failure

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UncompressMemory
bytes = unixCompress.UncompressMemory(inData) ' Variant

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

Returns a zero-length byte array (as a Variant) on failure.
An empty array will have a UBound of -1 meaning 0 elements.

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UncompressMemToFile
success = unixCompress.UncompressMemToFile(inData, destPath) ' Long (1/0)

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

Returns 1 for success, 0 for failure.

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UncompressString
str = unixCompress.UncompressString(inCompressedData, charset) ' String

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 Nothing on failure

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UnTarZ
success = unixCompress.UnTarZ(zFilename, destDir, bNoAbsolute) ' Long (1/0)

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 1 for success, 0 for failure.

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WriteFile
success = unixCompress.WriteFile(filename, binaryData) ' Long (1/0)

Convenience method for writing the contents of a byte array to a file.

Returns 1 for success, 0 for failure.

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