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If you need a little help understanding standard libraries ir shared modules in Linux then here we work with the Raspberry Pi and Raspbian Linux to show you how. We create a .so file from scratch and use it withing a program we link to the library. You will see ldd and ldconfig as well as the gcc options needed to make this work
so we dont need something like a .lib file? like you would on windows?
simply a .so is everything?
also if we end up specifying the path to the lib with -L<path_to_lib> when we compile at the end
then why do we need to bother with all the config nonsens in the first place?
Why is unistd.h included in standard.c? It is not used... I redid the tutorial with the following code files below. Advantage is that the main function and its module do not have to know any details about the implementation of the functions/methods in the shared object; just including the header file displayuid.h is enough.
echo "`date` Starting: $*"
echo "`date` Finished: $*"
echo "Press enter to continue"
command \rm *.o *.so
command gcc -c -fPIC displayuid.c -Wall
command gcc -shared -o libdisplayuid.so displayuid.o -Wall
command sudo cp libdisplayuid.so /usr/local/lib/tmp_lib_maot
command gcc -L /usr/local/lib/tmp_lib_maot/ standard.c -o standard.o -l displayuid -Wall
int realUid = getuid();
int euid = geteuid();
printf("The real UID= %d\n", realUid);
printf("The effective UID= %d\n", euid);
#endif // DISPLAYUID_H
printf("This is the main program\n");
Not really. C compilers won't complain, when there is an undefined reference. To be exact, there always are at the stage of compiling. Header files are just there to tell the compiler: "hey, yes, those functions, those will be added later, don't worry about them, just remember that those names aren't mistakes, and don't complain when you see them, good boy". Complaining about unresolved references is the job of linker. That's why, when you are using gcc from command line, you have to tell it where every single file of your code is. Gcc has no information about their location, nor does header files or any part of your code.
In this case, you will be compiling this code to a single object file, then it's a job of the linker that will link it with your program later, to resolve the references.
Thanks! I learned that C allowed "implicit declaration of functions" prior to C99. I'm a C++ person, so the fact that you can get away with using an undeclared symbol.
I understand you ommited the whole "header/prototype thing" for clarity, but perhaps you could have mentioned that. If you did, I'm sorry, I missed that.
Work out if you need to pay.
When you know your gain you need to work out if you need to report and pay Capital Gains Tax.
You may be able to work out how much tax to pay on your shares.
the same type, acquired in the same company on the same date sold at the same time.
sold other shares in the tax year sold other chargeable assets in the tax year, such as a property you let out claim any reliefs are a company, agent, trustee or personal representative.
Reporting a loss.
The rules are different if you need to report a loss.
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Rest of Europe etc.
Ratings from equity analysts covering the Danske Bank share and consensus earnings estimates.
Selling in special circumstances.
shares you bought at different times and prices in one company shares through an investment club shares after a company merger or takeover employee share scheme shares.
Jointly owned shares and investments.
If you sell shares or investments that you own jointly with other people, work out the gain for the portion that you own, instead of the whole value. There are different rules for investment clubs.
What to do next.