bionic (3) ofdstreambuf.3bobcat.gz
NAME
FBB::OFdStreambuf - Output stream buffer initialized by a file descriptor
SYNOPSIS
#include <bobcat/ofdstreambuf>
Linking option: -lbobcat
DESCRIPTION
FBB::OFdStreambuf objects may be used as a std::streambuf of std::ostream objects to allow insertions
into a file descriptor.
File descriptors are not defined within the context of C++, but they can be used on operating systems
that support the concept. Realize that using file descriptors introduces operating system dependencies.
NAMESPACE
FBB
All constructors, members, operators and manipulators, mentioned in this man-page, are defined in the
namespace FBB.
INHERITS FROM
std::streambuf
ENUMERATION
The public enumeration Mode defined in the class FBB::OFdStreamBuf has the following values:
o CLOSE_FD, indicating that the file descriptor used by the object must be closed;
o KEEP_FD (the default) indicating that the file descriptor used by the object must not be closed.
CONSTRUCTORS
o OFdStreambuf():
This constructor initializes the streambuf, without associating it to a file descriptor, and
without using buffering. The member open() can be used to associate the object later on with a
file descriptor and optionally a buffer size. When the object is destroyed or if the mode-less
overloaded version of the open member is called, the file descriptor will be closed.
o OFdStreambuf(Mode mode):
This constructor initializes the streambuf, without associating it to a file descriptor, and
without using buffering. The member open() can be used to associate the object later on with a
file descriptor and optionally a buffer size. When the object is destroyed or if the mode-less
overloaded version of the open member is called, the Mode argument determines whether the file
descriptor will be closed or will remain open.
o OFdStreambuf(int fd, size_t n = 1):
This constructor initializes the streambuf, associating it to file descriptor fd, and an optional
unget buffer size (by default having size 1). When open is called subsequently, or if the object
is destroyed the provided file descriptor will be closed.
o OFdStreambuf(int fd, size_t n = 1):
This constructor initializes the streambuf, associating it to file descriptor fd, and an optional
unget buffer size (by default having size 1). When the object is destroyed or if the mode-less
overloaded version of the open member is called, the file descriptor will be closed.
o OFdStreambuf(int fd, Mode mode, size_t n = 1):
This constructor initializes the streambuf, associating it to file descriptor fd, and an optional
unget buffer size (by default having size 1). When the object is destroyed or if the mode-less
overloaded version of the open member is called, the Mode argument determines whether the file
descriptor will be closed or will remain open. There are no copy or move constructors.
MEMBER FUNCTIONS
All members of std::streambuf are available, as FBB::OFdStreambuf inherits from this class. Some of the
std::streambuf’s member are overridden by FBB::OFdStreambuf, see below.
o void close():
The file descriptor used by the OFdStreambuf is closed, irrespective of the Mode that was
specified when the OFdStreambuf object was constructed. Following close the OFdStreambuf object
can no longer be used until one of its open members has been called.
o int fd() const:
The file descriptor used by the OFdStreambuf object is returned. If the OFdStreambuf is not
associated with a file descriptor -1 is returned.
o void open(int xfd, size_t n = 1):
The streambuf is (re)initialized, using file descriptor fd, and an optional unget buffer size (by
default having size 1). When called repeatedly, the Mode specification used whem the object was
constructed determines whether the file descriptor will be closed or will remain open.
o void open(int xfd, Mode mode, size_t n = 1):
The streambuf is (re)initialized, using file descriptor fd, a file descriptor closing parameter
and an optional unget buffer size (by default having size 1). Depending on the Mode argument the
object’s currently used file descriptor will be closed or will remain open when the IFdStreambuf
object is destroyed. The overloaded assignment operator is not available.
PROTECTED MEMBER FUNCTION
The member listed in this section implements the tasks of the comparably named virtual function in the
class’s private interface. This separates the redefinable interface from the user-interface. The class
OFdStreambuf can, in accordance with Liskov’s Substitution Principle, be used as a std:streambuf; but it
also offers a facility for classes deriving from OFdStreambuf. This facility is listed here.
o int pSync():
The contents of the OFdStreambuf’s internal buffer are flushed. If writing the contents to the
file descriptor fails, a warning message is displayed to the standard error stream.
EXAMPLE
To do
FILES
bobcat/ofdstreambuf - defines the class interface
SEE ALSO
bobcat(7), ifdstreambuf(3bobcat), ofdstream(3bobcat), std::streambuf
BUGS
None reported
DISTRIBUTION FILES
o bobcat_4.08.02-x.dsc: detached signature;
o bobcat_4.08.02-x.tar.gz: source archive;
o bobcat_4.08.02-x_i386.changes: change log;
o libbobcat1_4.08.02-x_*.deb: debian package holding the libraries;
o libbobcat1-dev_4.08.02-x_*.deb: debian package holding the libraries, headers and manual pages;
o http://sourceforge.net/projects/bobcat: public archive location;
BOBCAT
Bobcat is an acronym of `Brokken’s Own Base Classes And Templates’.
COPYRIGHT
This is free software, distributed under the terms of the GNU General Public License (GPL).
AUTHOR
Frank B. Brokken (f.b.brokken@rug.nl).