Provided by: umview_0.5-2_i386 bug


       umview - User Mode implementation of View-OS


       umview [ options ] prog


       The  main  goal  of the View-OS project is to give each process its own
       view of the system resources.  For  example,  each  process  can  mount
       filesystems  or  hide  some file or directories. It is also possible to
       assign virtual network  interfaces,  IP  addresses  or  define  virtual
       devices for each process (or for hierarchies of processes).
       umview  is  the  user mode implementation of View-OS concepts.  It is a
       modular partial virtual machine.  umview before loading any  module  is
       completely  transparent,  a  process  behaves inside umview as it would
       have behaved outside.  Each module  can  customize  specific  entities:
       there  are  modules  to  mount  filesystems at user-level (umfuse) , to
       define virtual network interfaces (lwipv6) , to define virtual  devices
       (umdev)  ,  to  provide  interpreters  for executables, e.g. to support
       executables for foreign  architectures  (umbinfmt)  ,  to  hide,  move,
       overlay parts of the file system (viewfs).
       These  are  some  examples  of  modules  provided  by the View-OS team.
       umview aims to provide a general interface to customize the system call
       semantics  of  process under specified conditions. So more modules will
       be added both by the View-OS team and by third parties.


       -V name
       --viewname name
           set the name of the view. The view can be read and set using vuname
           or viewname commands.
       -p module [ , module_options ]
       --preload module [ , module_options ]
           preload  modules.   Modules will be loaded as shared libraries thus
           all the rules to load libraries apply. Modules must be loaded  from
           a  directory within the search path or should be specified by
           their  pathnames.   If  necessary  configure  the   LD_LIBRARY_PATH
           environment  variable  appropriately.   module_options  are  module
           specific configuration options, thus the  reader  should  refer  to
           each service module manual for a complete description.  Modules can
           be loaded at run time using the um_add_service command.
           umview is able to provide module nesting, i.e. a module can provide
           services  on  the  basis  of  virtual  services provided by another
           module or even by the module itself. For example it is possible  to
           mount  a  file system image which is stored in an already virtually
           mounted filesystem.  This feature requires the  pure_libc  library.
           The -x or --nonesting option disables the nesting feature.
           umview  is  able  to  use  some  specific  kernel  extensions (when
           present) to increase its performance. The  source  distribution  of
           umview  include  the  kernel  patches  for the latest kernels.  The
           kernel extensions are enabled  by  default  when  available.   This
           option disables the kernel extensions.
           This option disables the PTRACE_MULTI kernel extension.
           This option disables the PTRACE_SYSVM kernel extension.
           This option disables the PTRACE_SYSVIEWOS kernel extension (already
           experimental, not yet released).
       -o file
       --output file
           This option diverts the debugging output to the file specified,  it
           is  useful when umview has been compiled with debugging extensions.
           Print the version and exit.
           Print a short help message and exit.


       um_add_service(1) um_del_service(1) um_ls_service(1)  um_mov_service(1)
       umfuse(1viewos)    lwipv6(1viewos)   umdev(1viewos)   umbinfmt(1viewos)
       viewfs(1viewos) vuname(1viewos) viewname(1viewos)


       View-OS is a project of the Computer Science Department, University  of
       Bologna.  Project Leader: Renzo Davoli. Development Team: P. Angelelli,
       A.  Bacchelli, M.  Belletti,  P.  Beverini,  D.  Billi,  A.  Forni,  L.
       Gardenghi,  A.  Gasparini,  D.  Lacamera,  C.  Martellini, A. Seraghiti

       Howto’s and further information  can  be  found  on  the  project  wiki