#include <FdInteractor.h>
class CFdInteractor {CFdInteractor(int fd);CFdInteractor(const CFdInteractor& rhs);CFdInteractor& operator=(const CFdInteractor& rhs);const int getFd();int Read(UInt_t nBytes, void* pBuffer);int Write(UInt_t nBytes, void* pData);void Flush();}
The CFdInteractor is an interactor that
accepts and, if requested, provides data to anything that can be
represented by a file descriptor. Reads and writes
go directly to the file descriptor, the only buffering that is
done is what is done by whatever handles the file descriptor at the
operating system level.
CFdInteractor(int fd);
Construct an object of this class connected to the
file descriptor fd.
CFdInteractor(const CFdInteractor& rhs);
Constructs a copy of the file descriptor
rhs. The underlying file descriptor
is duped so that the original one can be closed without
affecting the copy.
CFdInteractor& operator=(const CFdInteractor& rhs);
Assigns to this from the rhs.
The existing file descriptor is closed, and the file descriptor
associted with rhs is duped so that
actions by this object will be independent of those of the
rhs
const int getFd();
This informational member returns the file descriptor associated with the object.
int Read(UInt_t nBytes, void* pBuffer);
Attempts to read
nBytes of data from the file into
pBuffer. The actual number of bytes read
is returned as the value of the method. If 0
is returned, the fd has hit an eof or is in non-blocking mode with
no data ready to be read. If negative, an error condition
exists and the reason for the error will be in the global
variable/macro errno
int Write(UInt_t nBytes, void* pData);
Attempts to write
nBytes
of data from pData
to the file. The actual number of bytes of data written are
returned to the caller. If an error has occured, the result will
be negative. If the result is zero, likely the file descriptor
is open in non=blocking mode, but cannot now be written to
(e.g. it's a pipe without a reader).
void Flush();
Flushes any buffered output to the file. In practice this does nothing for file descriptors.