LZRead function

Reads (at most) the specified number of bytes from a file and copies them into a buffer.

Syntax

INT LZRead(
  INT  hFile,
  CHAR *lpBuffer,
  INT  cbRead
);

Parameters

hFile

A handle to the file.

lpBuffer

A pointer to a buffer that receives the bytes read from the file. Ensure that this buffer is larger than cbRead.

cbRead

The count of bytes to be read.

Return Value

If the function succeeds, the return value specifies the number of bytes read.

If the function fails, the return value is an LZERROR_* code. These codes have values less than zero. Note that LZRead calls neither SetLastError nor SetLastErrorEx; thus, its failure does not affect a thread's last-error code.

The following is the list of error codes that LZRead can return upon failure.

Return code Description
LZERROR_BADINHANDLE
The handle identifying the source file is not valid. The file cannot be read.
LZERROR_BADOUTHANDLE
The handle identifying the destination file is not valid. The file cannot be written.
LZERROR_BADVALUE
One of the input parameters is not valid.
LZERROR_GLOBALLOC
The maximum number of open compressed files has been exceeded or local memory cannot be allocated.
LZERROR_GLOBLOCK
The LZ file handle cannot be locked down.
LZERROR_READ
The source file format is not valid.
LZERROR_WRITE
There is insufficient space for the output file.
 

There is no extended error information for this function; do not call GetLastError.

Remarks

The handle identifying the file must be retrieved by calling either the LZInit or LZOpenFile function.

If the file is compressed, LZRead operates on an expanded image of the file and copies the bytes of data into the specified buffer.

In Windows 8 and Windows Server 2012, this function is supported by the following technologies.

Technology Supported
Server Message Block (SMB) 3.0 protocol Yes
SMB 3.0 Transparent Failover (TFO) Yes
SMB 3.0 with Scale-out File Shares (SO) Yes
Cluster Shared Volume File System (CsvFS) Yes
Resilient File System (ReFS) Yes
 

CsvFs will do redirected IO for compressed files.

Requirements

   
Windows version Windows XP [desktop apps only] Windows Server 2003 [desktop apps only]
Target Platform Windows
Header lzexpand.h (include Windows.h)
Library Lz32.lib
DLL Lz32.dll

See Also

File Compression and Decompression

File Management Functions

LZInit

LZOpenFile

LZSeek