NAME

       togeomview - send commands or OOGL objects to geomview

SYNOPSIS

       togeomview [-c] [-g]  [pipename  [program args ...]]

DESCRIPTION

       togeomview  sends  a  stream  of  geomview  commands,  or OOGL-format geometric data, to a
       cooperating copy of geomview.  If geomview is not running, it  is  automatically  started.
       ('geomview'  must  be  on  the $PATH of the user running 'togeomview' in order for this to
       work.)

       Typical usage is:
            someprogram | togeomview    (to send commands) or
            someprogram-generating-OOGL-data | togeomview -g  (to send geometry)
       i.e. a program pipes geometric data into ``togeomview''; the data is displayed by  a  copy
       of geomview run with the -M option and a name matching the one given to togeomview.

       Togeomview  uses a named pipe in the directory /tmp/geomview to communicate with geomview.
       If unspecified, the pipe's default name is "OOGL".  When sending geometry (-g), a geomview
       object with the same name as the pipe appears in geomview's object browser.

       By  default,  when  no suitable copy of geomview is running, togeomview invokes "geomview"
       with arguments specifying  the  appropriate  named  pipe.   A  different  command  may  be
       specified as in:

            togeomview  OOGL  gv -wpos 300x300 -c my_startup_script

       which  communicates  through  a  pipe  named OOGL, and (if necessary) invokes the given gv
       command.  The pipe name is required if a command is specified.

       After togeomview has created it, the named pipe may be written as an ordinary  file.   For
       example, one could use

            togeomview pipename < /dev/null

       to  invoke  a  listening  copy  of  geomview, and then run a program which simply wrote to
       /tmp/geomview/pipename.

FILES

       /tmp/geomview

BUGS

       The pipe-based communications scheme imposes several restrictions.

       If no copy of geomview is reading from the pipe, or if geomview gets far enough behind,  a
       program  writing  data  to  ``togeomview''  will  be  forced  to block after sending a few
       kilobytes.

       Because of the buffering in the pipe,  the  sender  may  be  substantially  ahead  of  the
       geomview display.

       If  geomview  exits, the sending program receives a write-on-broken-pipe (SIGPIPE) signal,
       which will kill it unless measures are taken to catch or ignore that signal.

       Only one copy of geomview can read from a given pipe at a time.  If a second copy attempts
       to  read  from it, both will probably fail.  It's fine to have multiple copies of geomview
       reading from different pipes.

       Note that togeomview will invoke geomview if no extant copy is listening to  the  relevant
       pipe; it can't connect to an existing copy of geomview started by other means.

SEE ALSO

       geomview(1), oogl(5)