help needed compiling lcnc2.9 on kubuntu 20.04 for sim

john@cave:~/emc/src$ ./configure --help
john@cave:~/emc/src$ ./configure --help
`configure' configures LinuxCNC 2.9.0~pre1 to adapt to many kinds of systems.

Usage: ./configure [OPTION]... [VAR=VALUE]...

To assign environment variables (e.g., CC, CFLAGS...), specify them as
VAR=VALUE.  See below for descriptions of some of the useful variables.

Defaults for the options are specified in brackets.

Configuration:
  -h, --help              display this help and exit
      --help=short        display options specific to this package
      --help=recursive    display the short help of all the included packages
  -V, --version           display version information and exit
  -q, --quiet, --silent   do not print `checking ...' messages
      --cache-file=FILE   cache test results in FILE [disabled]
  -C, --config-cache      alias for `--cache-file=config.cache'
  -n, --no-create         do not create output files
      --srcdir=DIR        find the sources in DIR [configure dir or `..']

Installation directories:
  --prefix=PREFIX         install architecture-independent files in PREFIX
                          [run-in-place]
  --exec-prefix=EPREFIX   install architecture-dependent files in EPREFIX
                          [PREFIX]

By default, `make install' will install all the files in
`run-in-place/bin', `run-in-place/lib' etc.  You can specify
an installation prefix other than `run-in-place' using `--prefix',
for instance `--prefix=$HOME'.

For better control, use the options below.

Fine tuning of the installation directories:
  --bindir=DIR            user executables [EPREFIX/bin]
  --sbindir=DIR           system admin executables [EPREFIX/sbin]
  --libexecdir=DIR        program executables [EPREFIX/libexec]
  --sysconfdir=DIR        read-only single-machine data [PREFIX/etc]
  --sharedstatedir=DIR    modifiable architecture-independent data [PREFIX/com]
  --localstatedir=DIR     modifiable single-machine data [PREFIX/var]
  --runstatedir=DIR       modifiable per-process data [LOCALSTATEDIR/run]
  --libdir=DIR            object code libraries [EPREFIX/lib]
  --includedir=DIR        C header files [PREFIX/include]
  --oldincludedir=DIR     C header files for non-gcc [/usr/include]
  --datarootdir=DIR       read-only arch.-independent data root [PREFIX/share]
  --datadir=DIR           read-only architecture-independent data [DATAROOTDIR]
  --infodir=DIR           info documentation [DATAROOTDIR/info]
  --localedir=DIR         locale-dependent data [DATAROOTDIR/locale]
  --mandir=DIR            man documentation [DATAROOTDIR/man]
  --docdir=DIR            documentation root [DATAROOTDIR/doc/linuxcnc]
  --htmldir=DIR           html documentation [DOCDIR]
  --dvidir=DIR            dvi documentation [DOCDIR]
  --pdfdir=DIR            pdf documentation [DOCDIR]
  --psdir=DIR             ps documentation [DOCDIR]

X features:
  --x-includes=DIR    X include files are in DIR
  --x-libraries=DIR   X library files are in DIR

System types:
  --build=BUILD     configure for building on BUILD [guessed]
  --host=HOST       cross-compile to build programs to run on HOST [BUILD]

Optional Features:
  --disable-option-checking  ignore unrecognized --enable/--with options
  --disable-FEATURE       do not include FEATURE (same as --enable-FEATURE=no)
  --enable-FEATURE[=ARG]  include FEATURE [ARG=yes]
  --enable-non-distributable
                          To build LinuxCNC even if a license problem would
                          render the resulting binaries non-distributable
                          under the terms of the LinuxCNC license
  --enable-simulator      Deprecated! Use --with-realtime=uspace instead.
  --enable-toolnml        Use nml for tooldata, default is mmap
  --disable-userspace-pci Disable userspace PCI access (use this if libudev is
                          unavailable).
  --disable-gtk           Disable the parts of LinuxCNC that depend on GTK.
  --disable-gtk2          Disable the parts of LinuxCNC that depend on GTK2.
                          Ónly needed for classicladder)
  --enable-build-documentation=FORMAT
                          Build documentation. FORMAT may be "Y" for both or
                          "pdf" or "html" if only one format is desired.
  --disable-build-documentation-translation
                          Disable building documentation in languages other
                          than English.
  --disable-check-runtime-deps
                          Skip checks for runtime requirements not needed
                          during the build process.
  --disable-nls           Don't use NLS.

Optional Packages:
  --with-PACKAGE[=ARG]    use PACKAGE [ARG=yes]
  --without-PACKAGE       do not use PACKAGE (same as --with-PACKAGE=no)
  --with-realtime=PATH    Path where RTAI is installed, or "uspace" for POSIX
                          userspace.
  --with-kernel-headers=PATH
                          Location for kernel headers.
  --with-libmodbus        Specify whether or not to build the drivers that use
                          libmodbus (defaults to "yes").
  --with-libusb-1.0       Specify whether or not to build the drivers that use
                          libusb-1.0 (defaults to "yes").
  --with-kbuild           Specify if your kernel uses kbuild or not.
  --with-module-dir=PATH  Installation directory for kernel modules.
  --with-rmmod=PATH       Location of the rmmod program to use.
  --with-insmod=PATH      Location of the insmod program to use.
  --with-boost[=ARG]      use Boost library from a standard location
                          (ARG=yes), from the specified location (ARG=<path>),
                          or disable it (ARG=no) [ARG=yes]
  --with-boost-libdir=LIB_DIR
                          Force given directory for boost libraries. Note that
                          this will override library path detection, so use
                          this parameter only if default library detection
                          fails and you know exactly where your boost
                          libraries are located.
  --with-boost-python     specify yes/no or the boost python library or suffix
                          to use
  --with-tclConfig=PATH   Specify the path to tclConfig.
  --with-tkConfig=PATH    Specify the path to tkConfig.
  --with-x                use the X Window System
  --with-locale-dir=DIR   Location of the locale file(s) [DATADIR/locale].

Some influential environment variables:
  CXX         C++ compiler command
  CXXFLAGS    C++ compiler flags
  LDFLAGS     linker flags, e.g. -L<lib dir> if you have libraries in a
              nonstandard directory <lib dir>
  LIBS        libraries to pass to the linker, e.g. -l<library>
  CPPFLAGS    (Objective) C/C++ preprocessor flags, e.g. -I<include dir> if
              you have headers in a nonstandard directory <include dir>
  CC          C compiler command
  CFLAGS      C compiler flags
  CPP         C preprocessor
  PYTHON_VERSION
              The installed Python version to use, for example '2.3'. This
              string will be appended to the Python interpreter canonical
              name.
  XMKMF       Path to xmkmf, Makefile generator for X Window System

Use these variables to override the choices made by `configure' or to help
it to find libraries and programs with nonstandard names/locations.

Report bugs to <emc-developers@lists.sourceforge.net>.

 ./configure no-docs uspace 
...
checking build system type... Invalid configuration `no-docs': machine `no-unknown' not recognized
configure: error: /bin/bash ./config.sub no-docs failed

./autogen.sh
./configure --enable-build-documentation=no
make
sudo make setuid
cd ..
. ./scripts/rip-environment
linuxcnc

./configure --disable-build-documentation