infox option
              Return  information about Extended Tcl, or the cur-
              rent  application.   The  following  infox  command
              options are available:

            version
                   Return  the  version  number  of Extended Tcl.
                   The version number for Extended Tcl is  gener-
                   ated  by  combining  the  base  version of the
                   standard Tcl code with a letter indicating the
                   version  of  Extended Tcl being used.  This is
                   the documentation for version 7.0a.

            patchlevel
                   Return the patchlevel for Extended Tcl.

            have_flock
                   Return 1 if the flock command defined,   0  if
                   it is not available.

            have_fsync
                   Return 1 if the fsync system call is available
                   and the  sync  command  will  sync  individual
                   files.   0 if it is not available and the sync
                   command will always sync all file buffers.

            have_msgcats
                   Return 1 if XPG message  catalogs  are  avail-
                   able,  0  if  they  are  not.   The catgets is
                   designed to continue to function without  mes-
                   sage  catalogs,  always  returning the default
                   string.

            have_posix_signals
                   Return 1 if Posix signals are available (block
                   and  unblock  options available for the signal
                   command).  0 is returned if Posix signals  are
                   not available.

            have_sockets
                   Return 1 if sockets are available (server_open
                   and server_info commands and fstat  removehost
                   option).   0  is  returned  if sockets are not
                   available.

            appname
                   Return the symbolic application  name  of  the
                   current  application  linked with the Extended
                   Tcl library.  The C variable  tclAppName  must
                   be  set by the application to return an appli-
                   cation specific value for this variable.

            applongname
                   Return a natural language name for the current
                   application.  The  C  variable  tclLongAppName
                   must be set by the application  to  return  an
                   application  specific value for this variable.

            appversion
                   Return the  version  number  for  the  current
                   application.   The  C  variable  tclAppVersion
                   must be set by the application  to  return  an
                   application-specific  value for this variable.

            apppatchlevel
                   Return the patchlevel for the current applica-
                   tion.  The C variable tclAppPatchlevel must be
                   set by the application to return  an  applica-
                   tion-specific value for this variable.

       This command is provided by Extended Tcl.