wy__rdbuf.3wy

一个不错

.\"
.\" Edited by I.J.Wang, 2005
.\"
.TH Wy__RdBuf 3wy "libwy v0.31"
.SH NAME
Wy__RdBuf \- Proxy class for reading data from WyByteFlow objects
.SH SYNOPSIS
.B #include <wy__rdbuf.h>
.PP
\fBWarning: This class is for internal testing use.\fP

Wy__RdBuf is a proxy class facilitating data reading from WyByteFlow object
by reading data through a queue buffer.
.SH "PUBLIC MEMBERS"
 class \fBReply\fP : public WyRet
 \fBWy__RdBuf\fP(WyByteFlow*)
 \fB~Wy__RdBuf\fP() throw()
 WyByteFlow* \fBrf_ptr\fP(void) const throw()
 WyCSeg \fBdata\fP(void) const throw()
 WyRet \fBreset\fP(WyByteFlow*)
 WyRet \fBgetch\fP(char&)
 WyRet \fBunget\fP(void)
 WyRet \fBgetdata\fP(WyCSeg&, size_t)
 WyRet \fBgetdata\fP(WyCSeg&, size_t, char)
 void \fBflush\fP(size_t)

 size_t \fB_rdsize\fP(void) const throw()
 void \fB_rdsize\fP(size_t) throw()
 WyRet \fB_feed\fP(void)
 WyRet \fB_feed\fP(size_t)
.SH "DESCRIPTION"
.\"--------------------------------------------
.PP
.BI "class Reply : public WyRet"
.PP
    Class specific throw type
.\"--------------------------------------------
.PP
.BI "Wy__RdBuf(WyByteFlow* " "bfp" ")"
.PP
    Construct object to read data from \fIbf\fP
 
    rf_ptr()= \fIbfp\fP (the pointer exactly the same as \fIbfp\fP)
      data()= Empty WyCSeg (zero size)
.PP 
    [\fBThrow\fP] Reply
            Wym_EBADF       Object is not valid for the operation
            Wym_ENOMEM      Not enough memory
.\"--------------------------------------------
.PP
.BI "~Wy__RdBuf() throw()"
.PP
    Destruct *this
.\"--------------------------------------------
.PP
.BI "WyByteFlow* rf_ptr(void) const throw()"
.PP
    Get the WyByteFlow object reference *this reads data from
    The returned referece is exactly the same as given to the
    constructor Wy__RdBuf(WyByteFlow&)
.PP
    [\fBRet\fP] The WyByteFlow object reference *this reads data from
.\"--------------------------------------------
.PP
.BI "WyCSeg data(void) const throw()"
.PP
    Get the data segment in the queue buffer. The data are those
    that have been read from the WyByteFlow object and not output
    by any getdata(..) members.

    Note: Dereference of the returned WyCSeg is valid before the 
          next non-const member call.
.PP
    [\fBRet\fP] WyCSeg indicating the read data in the queue buffer
.\"--------------------------------------------
.PP
.BI "WyRet reset(WyByteFlow* " "bfp" ")"
.PP
    Reset *this to the state as Wy__RdBuf(\fIbfp\fP)

    Note: Previously output queue data segment is invalidated
.PP
    [\fBRet\fP] Ok              Succeed.
          Wym_EBADF       Object is not valid for the operation
          Wym_ENOMEM      Not enough memory
.\"--------------------------------------------
.PP
.BI "WyRet getch(char& " "chr" ")"
.PP
    Get the next character from the queue buffer and store into \fIchr\fP
    
    If there is no data is in the buffer, a read request is send to
    feed the buffer

    Note: Previously output queue data segment is invalidated
.PP 
    [\fBRet\fP] Ok              Succeed
          Wym_EFAULT      No device attached
          Wym_ENOENT      End-of-file encountered
          Wym_EBADF       Object is not valid for the operation
          Wym_EFBIG       _rdsize() exceeds the maximum
          Wym_EINTR       Interrupted by a signal
          Wym_EAGAIN      Non-blocking I/O
          Wym_EIO         Low level I/O error
          Wym_EINVAL      Device is not suitable for reading
          Wym_ENOMEM      Not enough memory
.PP 
    [\fBRefer\fP] WyByteFlow::read(WyStr&,size_t,size_t&)
.\"--------------------------------------------
.PP
.BI "WyRet unget(void)"
.PP
    Put back the last character getch(&char) returned into the buffer
    
    Note: Previously output queue data segment is invalidated
.PP 
    [\fBRet\fP] Ok              Succeed
          Wym_EFAULT      No device attached
          Wym_ENOENT      No char to put back into the buffer
          Wym_EFBIG       buffer size would exceed the maximum
          Wym_ENOMEM      Not enough memory
.\"--------------------------------------------
.PP
.BI "WyRet getdata(WyCSeg& " "dseg" ", size_t " "count" ")"
.PP
    Get data by resetting \fIdseg\fP with at most \fIcount\fP bytes
    of characters of the data buffer. The output data segment is
    valid until next non-const member calls.
    
    If not enough data is in the buffer, read request of \fIcount\fP 
    or _dtsize, which is larger, is send to feed the buffer.

    If getdata returned \fIdseg\fP with size less than \fIcount\fP,
    End-Of file or a failure encountered.
    
    Note: Dereference of the returned \fIdseg\fP is valid before the
          next non-const member call.
.PP 
    [\fBRet\fP] Ok              Succeed
          Wym_EFAULT      No device attached
          Wym_EBADF       Object is not valid for the operation
          Wym_EFBIG       _rdsize() exceeds the maximum
          Wym_EINTR       Interrupted by a signal
          Wym_EAGAIN      Non-blocking I/O
          Wym_EIO         Low level I/O error
          Wym_EINVAL      Device is not suitable for reading
          Wym_ENOMEM      Not enough memory
.PP 
    [\fBRefer\fP] WyByteFlow::read(WyStr&,size_t,size_t&)
.\"--------------------------------------------
.PP
.BI "WyRet getdata(WyCSeg& " "dseg" ", size_t " "count" ", char " "term" ")"
.PP
    Get data by resetting \fIdseg\fP with at most \fIcount\fP bytes
    of characters of the data buffer unless the character \fIterm\fP
    is encountered. The output data segment is valid until next
    non-const member calls.
    
    If not enough data is in the buffer, read request of \fIcount\fP 
    or _dtsize, which is larger, is send to feed the buffer.

    If getdata returned \fIdseg\fP with size less than \fIcount\fP,
    End-Of file or a failure encountered.
    
    Note: Dereference of the returned \fIdseg\fP is valid before the
          next non-const member call.
.PP 
    [\fBRet\fP] Ok              Succeed
          Wym_EFAULT      No device attached
          Wym_EBADF       Object is not valid for the operation
          Wym_EFBIG       _rdsize() exceeds the maximum
          Wym_EINTR       Interrupted by a signal
          Wym_EAGAIN      Non-blocking I/O
          Wym_EIO         Low level I/O error
          Wym_EINVAL      Device is not suitable for reading
          Wym_ENOMEM      Not enough memory
.PP 
    [\fBRefer\fP] WyByteFlow::read(WyStr&,size_t,size_t&)
.\"--------------------------------------------
.PP
.BI "void flush(size_t " "n" ") throw()"
.PP
    Discard \fIn\fP bytes of the buffer.
.\"--------------------------------------------
.PP
.BI "size_t _rdsize(void) const throw()"
.PP
    Get the amount of bytes that *this reads with each request from
    the WyByteFlow object.
.PP
    [\fBRet\fP] The amount of bytes *this reads from the WyByteFlow object
.\"--------------------------------------------
.PP
.BI "void _rdsize(size_t " "count" ") throw()"
.PP
    Set the amount of bytes to \fIcount\fP that *this reads with each
    request from the WyByteFlow object. This member has no effect
    if \fIcount\fP is zero.
.\"--------------------------------------------
.PP
.BI "WyRet _feed(void)"
.PP
    Read at most _rdsize() bytes of data and append to the end of
    the queue buffer.
    
    Note: Previously output queue data segment is invalidated
.PP 
    [\fBRet\fP] Ok              Succeed
          Wym_EFAULT      No device attached
          Wym_EBADF       Object is not valid for the operation
          Wym_EFBIG       _rdsize() exceeds the maximum
          Wym_EINTR       Interrupted by a signal
          Wym_EAGAIN      Non-blocking I/O
          Wym_EIO         Low level I/O error
          Wym_EINVAL      Device is not suitable for reading
          Wym_ENOMEM      Not enough memory
.PP 
    [\fBRefer\fP] WyByteFlow::read(WyStr&,size_t,size_t&)
.\"--------------------------------------------
.PP
.BI "WyRet _feed(size_t& " "nbytes" ")"
.PP
    Read at most \fInbytes\fP bytes of data and append to the end of
    the queue buffer.
    
    Note: Previously output queue data segment is invalidated
.PP 
    [\fBRet\fP] Ok              Succeed
          Wym_EFAULT      No device attached
          Wym_EBADF       Object is not valid for the operation
          Wym_EFBIG       _rdsize() exceeds the maximum
          Wym_EINTR       Interrupted by a signal
          Wym_EAGAIN      Non-blocking I/O
          Wym_EIO         Low level I/O error
          Wym_EINVAL      Device is not suitable for reading
          Wym_ENOMEM      Not enough memory
.PP 
    [\fBRefer\fP] WyByteFlow::read(WyStr&,size_t,size_t&)
.\"--------------------------------------------
.SH "SEE ALSO"
.BR wybyteflow
.BR wystr
.BR wy_uty
.BR wytimespec
.BR wy_thread
.SH NOTE
Except added by this library, replys are converted from the errno 
an underlying C library function returned. Report of such replys
are brief from Linux Programmer's Manual. See the associated man page
for details.

Project is in development, http://sourceforge.net/projects/libwx