On Tue, 10 Mar 2020 10:30:59 +0000, The Natural Philosopher
 wrote:

>Are these messages happening at compile time or at link time?
>
>I suspect its not that these are not defined in the header but that you
>aren't linking in the wiringPi library at link time...
Maybe I should not use Geany, but compile and link manually in a
terminal window. Must find out how to do that then. Sorry for my
incompetance.

But I am using Geany, which under the "Build" main menu (among others)
have the options Compile, Build, Make, Make Custom Target, Make Object
and Execute.  No menu for linking. I am using Compile, Build and
Execute. After your reply I also tried Make.
I have now tried all the menu points listed above, with the following
results:
Compile, Make, Make Object all (with blink.c active in Geany) run
successfully.
Build gives the error messages described in my first message.
Execute results in a terminal window with thism text:
/tmp/geany_run_script_6LY5G0.sh: 7: /tmp/geany_run_script_6LY5G0.sh:
./blink: not found

Geany uses these compile commands for C++:
-Compile: g++ -Wall -c "%f"
-Build: g++ -Wall -o "%e" "%f"


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(program exited with code: 127)
Press return to continue


--
Jesper Kaas - jesperk@neindanke.online.no

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