build.doc says:
=== Optional build components
Having the following optional components on your system will enable
various additional capabilities and extensions:
|============================================================================
|C++ compiler | allows building libgpsmm C++ wrapper for client library
|Qt 4.53+ | allows building libQgpsmm C++ wrapper for client library
|(n)curses | curses screen-painting library, used by cgps and gpsmon
|pps-tools | adds support for the KPPS API, for improved timing
|libusb | Userspace access to USB devices
|============================================================================
Which, to my mind, implies that I do not need it.
But running scons:
sanjeev@impy-T450s:~/SRC/gpsd$ scons
scons: Reading SConscript files ...
scons version: 4.0.1
scons is running under Python version: 3.9.6.final.0
gpsd version: release-3.22-468-gcce496368
This system is: linux
Checking whether the C compiler works... (cached) yes
Checking if compiler accepts -pthread... (cached) yes
Checking whether the C++ compiler works... (cached) yes
Checking for C header file curses.h... (cached) yes
Checking pkg-config for ncurses... (cached) yes
Checking pkg-config for tinfo... (cached) yes
Checking pkg-config for libusb-1.0... (cached) yes
Checking for C library librt... (cached) yes
Checking for C library libnsl... (cached) yes
Checking for C library libsocket... (cached) no
Checking for C library libm... (cached) yes
Checking for C library libthr... (cached) no
Checking pkg-config for dbus-1... (cached) yes
Checking pkg-config for bluez... (cached) no
Turning off Bluetooth support, library not found.
Checking for C type in_port_t... yes
Checking whether SUN_LEN is declared... (cached) yes
Checking for C header file linux/can.h... (cached) yes
You have kernel CANbus available.
Checking if compiler is C11... yes
Checking whether __STDC_NO_ATOMICS__ is declared... (cached) no
Checking for C header file stdatomic.h... (cached) yes
Checking whether __ORDER_BIG_ENDIAN__ is declared... (cached) yes
Checking whether __ORDER_LITTLE_ENDIAN__ is declared... (cached) yes
Checking whether __BYTE_ORDER__ is declared... (cached) yes
Your compiler has built-in endianness support.
Checking for C header file arpa/inet.h... (cached) yes
Checking for C header file netdb.h... (cached) yes
Checking for C header file netinet/in.h... (cached) yes
Checking for C header file netinet/ip.h... (cached) yes
Checking for C header file sys/sysmacros.h... (cached) yes
Checking for C header file sys/socket.h... (cached) yes
Checking for C header file sys/un.h... (cached) yes
Checking for C header file syslog.h... (cached) yes
Checking for C header file termios.h... (cached) yes
Checking for C header file winsock2.h... (cached) no
Checking if sizeof(time_t) is 64 bits... yes
Checking for C function cfmakeraw()... yes
Checking for C function clock_gettime()... yes
Checking for C function daemon()... yes
Checking for C function fcntl()... yes
Checking for C function fork()... yes
Checking for C function getopt_long()... yes
Checking for C function gmtime_r()... yes
Checking for C function inet_ntop()... yes
Checking for C function strlcat()... no
Checking for C function strlcpy()... no
Checking for C function strptime()... yes
Checking for C function sincos()... yes
Checking for C header file sys/timepps.h... (cached) yes
Checking whether TIOCMIWAIT is declared... (cached) yes
Checking for C library libdbus-1... yes
WARNING: AsciiDoctor not found.
WARNING: Some documentation and html will not be built.
Checking pkg-config for QtNetwork... (cached) no
Turning off Qt support, library not found.
Checking if compiler accepts -Wall... yes
Checking if compiler accepts -Wcast-align... yes
Checking if compiler accepts -Wextra... yes
Checking if compiler accepts -Wimplicit-fallthrough... yes
Checking if compiler accepts -Wmissing-declarations... yes
Checking if compiler accepts -Wmissing-prototypes... yes
Checking if compiler accepts -Wno-missing-field-initializers... yes
Checking if compiler accepts -Wno-uninitialized... yes
Checking if compiler accepts -Wpointer-arith... yes
Checking if compiler accepts -Wreturn-type... yes
Checking if compiler accepts -Wstrict-prototypes... yes
Checking if compiler accepts -Wvla... yes
Checking whether coverage program exists...no
Checking whether cppcheck program exists...no
Checking whether dia program exists...no
Checking whether flake8 program exists...no
Checking whether pycodestyle program exists...no
Checking whether pylint program exists...no
Checking whether scan-build program exists...no
Checking whether tar program exists.../usr/bin/tar
Checking whether valgrind program exists...no
Program coverage not found -- skipping Python coverage
Program cppcheck not found -- skipping cppcheck checks
Program dia not found -- not rebuiding cycle.svg.
Program flake8 not found -- skipping flake8 checks
Program pycodestyle not found -- skipping pycodestyle checks
Program pylint not found -- skipping pylint checks
Program scan-build not found -- skipping scan-build checks
Program valgrind not found -- skipping valgrind checks
Checking whether python program exists...no
Target Python doesn't exist - disabling Python.
Altered configuration variables:
bluez = False (default True): BlueZ support for Bluetooth devices
qt = False (default True): build Qt bindings
nostrip = True (default False): don't symbol-strip binaries at link time
python = False (default True): build Python support and modules.
manbuild = 0 (default auto): build help in man and HTML formats. No/Auto/Yes.
prefix = /usr (default /usr/local): installation directory prefix
python_libdir = /usr/lib/python3/dist-packages (default ): Python module directory prefix
docdir = /usr/share/doc/gpsd (default share/gpsd/doc): documents directory
Package libusb-1.0 was not found in the pkg-config search path.
Perhaps you should add the directory containing `libusb-1.0.pc'
to the PKG_CONFIG_PATH environment variable
No package 'libusb-1.0' found
OSError: 'pkg-config --cflags --libs libusb-1.0' exited 1:
File "/home/sanjeev/SRC/gpsd/SConstruct", line 63:
SConscript('SConscript',