wybyteflow.3wy

一个不错

          (If *this is a standard i/o handler,
           the following errors may also occur)

          Wym_EINTR       A signal had occurred
          Wym_EBUSY       Device or resource busy

    Note: Error report from closing the previously handled
          object is ignored. Use reset() first if the close
          return status is desired
.PP 
    [\fBRefer\fP] ::dup(int), ::dup2(int,int)
.\"--------------------------------------------
.PP
.BI "virtual WyRet reset(const char* " "pathname" ",int " "f" ")" 
.PP
.BI "virtual WyRet reset(const WyStr& " "pathname" ",int " "f" ")" 
.PP
    Reconstruct *this to the state as WyByteFlow(\fIpathname\fP,\fIf\fP)

      \fIf\fP= flags for ::open, except O_CREAT
.PP
    [\fBRet\fP] Ok              Succeed.
          Wym_EINVAL      \fIf\fP invalid
          Wym_EBADF       File is not valid for the operation
          Wym_EACCES      Search permission is denied
          Wym_ENAMETOOLONG \fIpathname\fP too long
          Wym_ENOENT      \fIpathname\fP does not exist
          Wym_ENOTDIR     Entry in \fIpathname\fP is not a directory
          Wym_EMFILE      Too many open fd
          Wym_ENFILE      File table overflow
          Wym_ENOMEM      Not enough memory
          Wym_EEXIST      Pathname already exists
          Wym_EINTR       Interrupted by a signal
          Wym_ENOSPC      Device left no space for the operation
          Wym_ENXIO       No such device (device not ready)
          Wym_EROFS       Read-only file system
          Wym_ENODEV      No such device
          Wym_ELOOP       Too many symbolic links encountered
          ...             reply converted from ::open

          (If *this is a standard i/o handler,
           the following errors may also occur)

          Wym_EBUSY       Device or resource busy

    Note: Error report from closing the previously handled
          object is ignored. Use reset() first if the close
          return status is desired
.PP 
    [\fBRefer\fP] ::open(const char*,int), ::dup2(int,int)
.\"--------------------------------------------
.PP
.BI "virtual WyRet _swap(WySysFile& " "sysf" ") throw()"
.PP
    Interchange state of *this with \fIsysf\fP
.PP
    [\fBRet\fP] Ok              Succeed
          Wym_EBADTYPE    \fIsysf\fP is not the same type as *this
.\"--------------------------------------------
.PP
.BI "virtual WyByteFlow* _alloc(WyRet& " "r" ") const"
.PP
    Allocate a default object of the most inherited type that
    *this refers.

    Note: Inhertied class must override this member

    \fIr\fP is reset with the return status:
            Wym_ENOMEM      Not enough memory
            Wym_ENOSYS      *Not overridden
            ...             Same from constructing WyByteFlow()

    A typical _alloc reimplemet example:

      D* D::_alloc(WyRet& r) const 
       try {
        if(typeid(*this)!=typeid(D)) {
          r=Wym_ENOSYS; WY_HERE(r);    // Set r to Wym_ENOSYS if the
          return(NULL);                // deriving class does not 
        }                              // override this member
        D *p= new(std::nothrow) D();
        if(p==NULL) {
          r=Wym_ENOMEM; WY_HERE(r);
        } else {
          r=Ok;
        }
        return(p);
      }
      catch(const Reply& e) {           // Assume D uses Reply
        r=e; WY_HERE(r);
        return(NULL);
      }
      catch(const WyRet& e) {           // Rethrow object of WyRet
        WY_THROW( WyRet(e) );           // family to the exact
      };                                // WyRet class
.PP
    [\fBRet\fP] Pointer of the allocated object, or NULL if failed.
          User is responsible to \fBdelete\fP the returned object.
.\"--------------------------------------------
.PP
.BI "virtual WyRet read(void* " "buf" ", size_t " "count" ", size_t& " "n_read" ")"
.PP
    Read at most \fIcount\fP bytes of data into memory pointed by \fIbuf\fP.

    \fIn_read\fP is always written with the bytes read and stored 
    into \fIbuf\fP.
.PP
    [\fBRet\fP] Ok              Succeed
          Wym_EBADF       Object is not valid for the operation
          Wym_EFBIG       \fIcount\fP exceeds the maximum
          Wym_EINTR       Interrupted by a signal before any data read
          Wym_EAGAIN      Non-blocking I/O (no data read)
          Wym_EIO         Low level I/O error
          Wym_EINVAL      Device is not suitable for reading
          Wym_EFAULT      \fIbuf\fP is inaccessible
          Wym_ENOMEM      Not enough memory for \fIcount\fP
.PP 
    [\fBRefer\fP] ::read(int,void*,size_t)
.\"--------------------------------------------
.PP
.BI "virtual WyRet read(WyStr&" " buf" ", size_t " "count" ", size_t& " "n_read" ")"
.PP
    Read at most \fIcount\fP bytes of data and \fBappend\fP to \fIbuf\fP.

    \fIn_read\fP is always written with the bytes read and appended 
    to \fIbuf\fP.
.PP
    [\fBRet\fP] Ok              Succeed
          Wym_EBADF       Object is not valid for the operation
          Wym_EFBIG       \fIcount\fP exceeds the maximum
          Wym_EINTR       Interrupted by a signal before any data read
          Wym_EAGAIN      Non-blocking I/O (no data read)
          Wym_EIO         Low level I/O error
          Wym_EINVAL      Device is not suitable for reading
          Wym_ENOMEM      Not enough memory for \fIcount\fP
.PP 
    [\fBRefer\fP] ::read(int,void*,size_t)
.\"--------------------------------------------
.PP
.BI "virtual WyRet write(const void* " "buf" ", size_t " "count" ", size_t& " "n_written" ")"
.PP
    Write \fIcount\fP bytes of data in \fIbuf\fP to the device.

    The number of written bytes is always stored into \fIn_written\fP
.PP
    [\fBRet\fP] Ok              Succeed
          Wym_EBADF       Object is not valid for the operation
          Wym_EINVAL      Object attatched device is not suitable
          Wym_EFAULT      \fIbuf\fP is inaccessible
          Wym_EFBIG       Attempt to write beyond the device limit 
          Wym_EPIPE       Write to a pipe or FIFO with no reader
          Wym_EAGAIN      Non-blocking I/O (write would block)
          Wym_EINTR       Interrupted by a signal before data written
          Wym_ENOSPC      Device left no space for the operation
          Wym_EIO         Low level I/O error
.PP 
    [\fBRefer\fP] ::write(int,const void*,size_t)
.\"--------------------------------------------
.PP
.BI "virtual WyRet write(WyCSeg " "buf" ", size_t& " "n_written" ")"
.PP
    Write data indicated by \fIbuf\fP to the device

    The number of written bytes is always stored into \fIn_written\fP
.PP
    [\fBRet\fP] Ok              Succeed
          Wym_EBADF       Object is not valid for the operation
          Wym_EINVAL      Object attatched device is not suitable
          Wym_EFBIG       Attempt to write beyond the device limit 
          Wym_EPIPE       Write to a pipe or FIFO with no reader
          Wym_EAGAIN      Non-blocking I/O (write would block)
          Wym_EINTR       Interrupted by a signal before data written
          Wym_ENOSPC      Device left no space for the operation
          Wym_EIO         Low level I/O error
.PP 
    [\fBRefer\fP] ::write(int,const void*,size_t)
.\"--------------------------------------------
.PP
.BI "virtual WyRet write(const WyStr& " "buf" ", size_t& " "n_written" ")"
.PP
    Write data in \fIbuf\fP to the device.

    The number of written bytes is always stored into \fIn_written\fP
.PP
    [\fBRet\fP] Ok              Succeed
          Wym_EBADF       Object is not valid for the operation
          Wym_EINVAL      Object attatched device is not suitable
          Wym_EFBIG       Attempt to write beyond the device limit 
          Wym_EPIPE       Write to a pipe or FIFO with no reader
          Wym_EAGAIN      Non-blocking I/O (write would block)
          Wym_EINTR       Interrupted by a signal before data written
          Wym_ENOSPC      Device left no space for the operation
          Wym_EIO         Low level I/O error
.PP 
    [\fBRefer\fP] ::write(int, const void*,size_t)
.\"--------------------------------------------
.PP
.BI "WyRet _fsync(void)"
.PP
    Wait untill all the in-core parts of *this associated file has
    written to device
.PP
    [\fBRet\fP] Ok              Succeed.
          Wym_EBADF       Object is not valid for writting
          Wym_EIO         Low level I/O error
          Wym_EINVAL      Device is not suitable for the operation
          Wym_EROFS       Read-only file system
.PP 
    [\fBRefer\fP] ::fsync(int)
.\"--------------------------------------------
.PP
.BI "WyRet _fdatasync(void)"
.PP
    Wait untill the in-core written data has written to device
.PP
    [\fBRet\fP] Ok              Succeed.
          Wym_EBADF       Object is not valid for writting
          Wym_EIO         Low level I/O error
          Wym_EINVAL      Device is not suitable for the operation
          Wym_EROFS       Read-only file system
.PP 
    [\fBRefer\fP] ::fdatasync(int)
.\"--------------------------------------------
.PP
.BI "WyRet _tcdrain(void)" 
.PP
    Wait until all output written to *this associated terminal device
    has been transmitted.
.PP
    [\fBRet\fP] Ok              Succeed.
          Wym_EBADF       Object is not valid for the operation
          Wym_EINTR       Interrupted by a signal
          Wym_ENOTTY      Not a terminal device
          ...             reply converted from the errno ::tcdrain
                          returned
.PP 
    [\fBRefer\fP] ::tcdrain(int)
.\"--------------------------------------------
.PP
.BI "bool _isatty(void) const" 
.PP
    Is *this referring to a terminal device
.PP
    [\fBRet\fP] true= *this refers to a terminal
         false= otherwise
.PP 
    [\fBRefer\fP] ::isatty(int)
.\"--------------------------------------------
.SH "SEE ALSO"
.BR wy
.BR wy_uty
.BR wyret
.BR wyfilestat
.BR wysysfile
.BR wychrfile
.BR wyregfile
.BR wytimespec
.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