IReader Class Reference
[C++ IOStream Fixups And Utilities]

Search Toolkit Book for IReader

#include <reader_writer.hpp>

Inheritance diagram for IReader:

[legend]List of all members.

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Detailed Description

A very basic data-read interface.

Definition at line 68 of file reader_writer.hpp.

Public Member Functions
virtual ERW_Result	Read (void *buf, size_t count, size_t *bytes_read=0)=0
	Read as many as "count" bytes into a buffer pointed to by "buf" argument.
virtual ERW_Result	PendingCount (size_t *count)=0
	Via parameter "count" (which is guaranteed to be supplied non-NULL) return the number of bytes that are ready to be read from input device without blocking.
virtual	~IReader ()

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Constructor & Destructor Documentation

virtual IReader::~IReader (   )  [inline, virtual]

Definition at line 91 of file reader_writer.hpp.

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Member Function Documentation

virtual ERW_Result IReader::PendingCount (  size_t *  count  )  [pure virtual]

Via parameter "count" (which is guaranteed to be supplied non-NULL) return the number of bytes that are ready to be read from input device without blocking. Return eRW_Success if the number of pending bytes has been stored at the location pointed to by "count". Return eRW_NotImplemented if the number cannot be determined. Otherwise, return other eRW_... condition to reflect the problem. Note that if reporting 0 bytes ready, the method may return either both eRW_Success and zero *count, or return eRW_NotImplemented alone. Implemented in CBDB_BlobReaderWriter, CCgiEntryReader, CSocketReaderWriter, CStringOrBlobStorageReader, CNetCacheSock_RW, CNetCacheReader, CFileReader, CFileReaderWriter, CStreamReader, CStringReader, CBlobReader, CNlmZipReader, CTransmissionReader, CBDB_CacheIReader, CCGIStreamReader, CDBAPI_CacheIReader, CxBlobReader, and CTarReader. Referenced by CTransmissionReader::PendingCount(), and CRWStreambuf::showmanyc().

virtual ERW_Result IReader::Read (  void *  buf, size_t  count, size_t *  bytes_read = 0 )  [pure virtual]

Read as many as "count" bytes into a buffer pointed to by "buf" argument. Store the number of bytes actually read, or 0 on EOF or error, via the pointer "bytes_read", if provided. Special case: if "count" passed as 0, then the value of "buf" is ignored, and the return value is always eRW_Success, but no change should be actually made to the state of input device. Implemented in CBDB_BlobReaderWriter, CCgiEntryReader, CSocketReaderWriter, CStringOrBlobStorageReader, CNetCacheSock_RW, CNetCacheReader, CFileReader, CFileReaderWriter, CStreamReader, CStringReader, CBlobReader, CNlmZipReader, CTransmissionReader, CBDB_CacheIReader, CCGIStreamReader, CDBAPI_CacheIReader, CxBlobReader, and CTarReader. Referenced by CTransmissionReader::Read(), CNlmZipReader::Read(), CIRByteSourceReader::Read(), CRWStreambuf::underflow(), CNlmZipReader::x_Read(), CNetCacheAPI::x_ReadBuffer(), CTransmissionReader::x_ReadRepeated(), CNlmZipReader::x_ReadZipHeader(), and CRWStreambuf::xsgetn().

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The documentation for this class was generated from the following file:

• include/corelib/reader_writer.hpp

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