NAME

       FBB::SharedMutex - Mutex for shared memory

SYNOPSIS

       #include <bobcat/sharedmutex>
       Linking option: -lpthread, -lbobcat

DESCRIPTION

       Shared   memory  may  be  used  by  multiple  processes.  To  synchronize  access  to  shared  memory  an
       FBB::SharedMutex may be defined inside a shared memory segment. An  FBB::SharedMutex  allows  clients  to
       lock  a  shared  memory  segment  before  reading  or  writing  its  contents.  E.g.,  the  Bobcat  class
       FBB::SharedSegment defines a SharedMutex in its shared memory segment.

       The FBB::SharedMutex class uses the facilities offered by the PThread library to implement shared  memory
       locking. To force unlocking a (possibly) locked shared memory segment, its destructor can be called.

NAMESPACE

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

INHERITS FROM

       -

CONSTRUCTORS

       o      SharedMutex():
              The default constructor initializes an FBB::SharedMutex object to a shared memory mutex (using the
              PTHREAD_PROCESS_SHARED attribute). As an FBB::SharedMutex object will normally be defined inside a
              shared memory segment the object’s memory is already available. In this case placement new  should
              be  used  to  call  the  constructor.  E.g., if a shared memory segment is attached to the current
              process at d_shared, and an FBB::SharedMutex should be defined at  d_shared’s  address,  then  the
              FBB::SharedMutex object can be initialized like this:

                  new (d_shared) FBB::SharedMutex;

              The copy and move constructors are not available.

       The  class’s  destructor  releasea  all  of  the current process’s nested shared memory segment locks. To
       destroy an FBB::SharedMuted object that has been constructed using the placement new operator use

           d_sharedMutex->~SharedMutex();

       (assuming  SharedMutex  *d_sharedMutex  points  to  the  location  where  placement  new  has  previously
       initialized the FBB::SharedMutex object.)

MEMBER FUNCTIONS

       o      void lock() const:
              When returning from this member, the current process has locked the shared memory segment.

       o      void unlock() const:
              The object’s lock of the shared memory segment is released.

EXAMPLE

       See the sharedstream(3bobcat) man page.

FILES

       bobcat/sharedmutex - defines the class interface

SEE ALSO

       bobcat(7)  isharedstream(3bobcat),  osharedstream(3bobcat),  sharedblock(3bobcat), sharedmemory(3bobcat),
       sharedpos(3bobcat), sharedsegment(3bobcat), sharedstream(3bobcat), sharedstreambuf(3bobcat)

BUGS

       None Reported.

DISTRIBUTION FILES

       o      bobcat_3.19.01-x.dsc: detached signature;

       o      bobcat_3.19.01-x.tar.gz: source archive;

       o      bobcat_3.19.01-x_i386.changes: change log;

       o      libbobcat1_3.19.01-x_*.deb: debian package holding the libraries;

       o      libbobcat1-dev_3.19.01-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).

libbobcat-dev_3.19.01-x.tar.gz                      2005-2013                          FBB::SharedMutex(3bobcat)