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Full Discussion: File Descriptor to File Name
Top Forums UNIX for Dummies Questions & Answers File Descriptor to File Name Post 93195 by jim mcnamara on Friday 16th of December 2005 10:09:11 AM
Old 12-16-2005
blowtorch has it right.

The file descriptor structure in memory does not have an actual name of a file in it.
Once you have a file open you can get some information about the file use lstat or fpathconf. Just not the file name. The reason is that the fd keeps track of files by inode number. If you translate and inode to a file name it will have disk device names
as part of the path. You referenced the file thru the filesystem - with a path and a name.

The other issue is: what do you want to do with the file name? You can do absolutely any defined file operation using the fd number.

If you need the path as you received it, then reference it with a global char * pointer.
 

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LEARN ABOUT CENTOS

ifdstream

FBB::IFdStream(3bobcat) 				   File Descriptor Input Stream 				   FBB::IFdStream(3bobcat)

NAME

       FBB::Ifdstream - Input Stream initialized by a File Descriptor

SYNOPSIS

       #include <bobcat/ifdstream>

DESCRIPTION

       FBB::IFdStream objects may be used to extract information from a device whose file descriptor is available.

       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.

       Note that sockets can be used as file descriptors.

NAMESPACE

       FBB
       All constructors, members, operators and manipulators, mentioned in this man-page, are defined in the namespace FBB.

INHERITS FROM

       std::istream

CONSTRUCTORS

       o      IFdStream(int fd, size_t n = 1):
	      The constructor initializes the object to read from descriptor fd, using a buffer of size n, by default having  size  1.	 The  copy
	      constructor is not available.

MEMBER FUNCTIONS

       All members of std::istream are available, as FBB::IFdStream inherits from this class. There are no additional members.

EXAMPLE

       See the clientsocket(3bobcat) man-page for an example showing how to use IFdStream.

FILES

       bobcat/ifdstream - defines the class interface

SEE ALSO

       bobcat(7), ifdstreambuf(3bobcat), ofdstream(3bobcat)

BUGS

       The  IFdStream  object uses a IFdStreamBuf for its std::streambuf. This buffer is associated with the file descriptor passed to IFdStream's
       constructor. When the IFdStream object goes out of scope the device (file, socket, etc.) to which the file descriptor that  was	passed	to
       IFdStream's constructor is not closed.

DISTRIBUTION FILES

       o      bobcat_3.01.00-x.dsc: detached signature;

       o      bobcat_3.01.00-x.tar.gz: source archive;

       o      bobcat_3.01.00-x_i386.changes: change log;

       o      libbobcat1_3.01.00-x_*.deb: debian package holding the libraries;

       o      libbobcat1-dev_3.01.00-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).

libbobcat1-dev_3.01.00-x.tar.gz 				     2005-2012						   FBB::IFdStream(3bobcat)
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