链接接线Pi Shared Object 库，用于 Ubuntu 20.04 中的 RPI4

Question

I'm hoping someone can help me look into something that I think should be somewhat trivial.

I'm simply trying to compile a cpp file that includes wiringPi.h:

#include <wiringPi.h>

int main(){ return 0; }

I've run tens of different commands with different linking parameters and no matter what it always says:

testing_spi.cpp:2:10: fatal error: wiringPi.h: No such file or directory
    2 | #include "wiringPi.h"
      |          ^~~~~~~~~~~~
compilation terminated.

For example,

g++ -lwiringPi -o test test.cpp
g++ -L/usr/lib/aarch64-linux-gnu -lwiringPi -o test_spi testing_spi.cpp
...

All resulting in the same output. I've been at this for a few hours and am confused why it's not linking.

The first g++ example was ran after installing wiringPi as stated on the website 'sudo apt install wiringPi'. After that didn't work, I noticed Ubuntu came with a pre-installed version (ver2):

sudo apt list --installed | grep wiring

WARNING: apt does not have a stable CLI interface. Use with caution in scripts.

libwiringpi2/focal,now 2.50-0ubuntu1 arm64 [installed]
wiringpi/focal,now 2.50-0ubuntu1 arm64 [installed]

But the only documentation I could find from Ubuntu is trash: https://packages.ubuntu.com/focal/amd64/libwiringpi2/filelist I was able to find those shared object files inside the directory "/usr/lib/aarch64-linux-gnu/". I'm just assuming it get included the same way "wiringPi.h" but I've also tried some guesses "libwiringPi.h", "wiringPi2.h", etc.

When I look inside the.so.2 file, I see some functions that I would like to get my hands on:

nm -gD --demangle /usr/lib/aarch64-linux-gnu/libwiringPi.so.2
                 w _ITM_deregisterTMCloneTable
                 w _ITM_registerTMCloneTable
                 U __ctype_b_loc
                 w __cxa_finalize
                 U __errno_location
                 U __fprintf_chk
                 w __gmon_start__
                 U __printf_chk
                 U __snprintf_chk
                 U __sprintf_chk
                 U __stack_chk_fail
                 U __stack_chk_guard
                 U __vsnprintf_chk
000000000000b910 T _drcSetupNet
0000000000023fd0 B _wiringPiClk
0000000000023fb8 B _wiringPiGpio
0000000000023fb0 B _wiringPiPads
0000000000023fc0 B _wiringPiPwm
0000000000023fd8 B _wiringPiTimer
0000000000023fc8 B _wiringPiTimerIrqRaw
                 U access
000000000000a180 T ads1115Setup
0000000000005b98 T analogRead
0000000000005bd8 T analogWrite

But I've having too much trouble trying to get it to link properly. Any help would be appreciated on this. I've been staring at this way too long.

I would also use the website version of wiringPi but couldn't locate any of the library files after running sudo apt install wiringPi . I'll be happy to get either version working for me. Thanks in advance!

Answer 1

After digging in deeper to why no headers are installed. I guess headers aren't included unless it's a '-dev' package. So I found this package instead: https://packages.ubuntu.com/hirsute/libwiringpi-dev which has the headers that let me compile without error. I still have to try out some functions but that would be separate issue I think.