I am relatively new to programming&C++ and just began learning about MYSQL. I have been searching for a couple of days but couldn't find a solution. I usually use Cygwin&VIM&g++ to write, compile and run codes that I write.
My goal is to retrieve data from MYSQL database that I've set up on my laptop and be able to run a simple algorithm on that data and possibly update the database.
I went into MYSQL's website and went through tutorials and found an example here. I have Boost, Connector, MYSQL server lib downloaded. When I run it, I get an error saying 'connection.h' was not found. I'm sure this is because when I compile it, g++ does not have the location of the library added to the search path that it goes through. The example has something like:
#include <cppconn/conneciton.h>
where these angled brackets means it is going to search (after the current directory) the standard search directory. I am guessing I have to add a new path (the location of where the libraries are) so that the compiler looks at that standard directory and compiles the header.
Through googling I am thinking in g++ I can use -Ldir -I to add a new search path but I don't get how to use it. Can anyone kindly explain/show me (by example) how to get over with this problem? :(
An #include issue would be solved with -I (-L is for a library if it is needed but first you have to get through the compile).
You need to figure out where the headers were installed (likely somewhere under either /usr/include or /usr/local/include/), and then add a -I with that directory, it may also be that you need to install a development package, many *nix distributions split based on runtime-build time distinctions.
And note also with the -I that the package may do something like install to /usr/include/libraryname/libname_version/libname in such a case you would only want to add -I/usr/include/libraryname/libname_version/ and then in your source file have #include
Related
I've downloaded Boost and am trying to get it into my XCode C++ project. (I only need filesystem, by the way.) I'm trying to follow these instructions but am finding them unclear.
Where it says to put /path/to/boost/include, I put /Documents/boost_1_57_0/boost; and where it says to put /path/to/boost/lib, I put /Documents/boost_1_57_0/libs.
(1) I'm not sure whether the above is correct. Is it?
(2) The next step tells me to add the .dylib file to the project. Where can I find that file? I've looked in almost every subfolder of boost_1_57_0 and can't find it.
(3) If the instructions on that site suck, can someone here give me better instructions?
When you install boost library through command window, it will tell you where the header files and lib files are stored. Instead of /Documents/boost_1_57_0/libs use /Documents/boost_1_57_0/stage/lib.You will find libboost_serialization.dylib in /Documents/boost_1_57_0/stage/lib. It should work for you.
Also go through this link :
https://buddypanda.com/?p=10
This has better explanation.
Very recently, I had this idea to start using Mozilla NSS and to learn to use it, so that somewhere in the future, i can use it, or can atleast start contributing to it.
So i went to its Website and cloned it source code into a director "NSS" using mercurial
Then I used
make nss_build_all
instead of
gmake nss_build_all
Note : I don't know, if it makes a difference, gmake is just GNU Make
This make command created a dist folder outside the nss folder. So, Now my NSS folder has 3 folders nss,nspr,dist.
In .bashrc i added a line at the end
export LD_LIBRARY_PATH=/home/ayusun/workspace/NSS/dist/Linux3.5_x86_glibc_PTH_DBG.OBJ/lib
Then i went over to this Sample code, did a copy paste and saved it in my NSS Folder.
And then i tried to compile it, but it failed, stating it couldn't find iostream.h, I went over and changed the location of header files
So
<iostream.h> became <iostream>
"pk11pub.h" became "nss/lib/pk11wrap/pk11pub.h"
"keyhi.h" became "nss/lib/cryptohi/keyhi.h"
"nss.h" became "nss/lib/nss/nss.h"
I tried compiling again but this time error came, that it couldn't find "planera.h"
which is actually present in dist/*.OBJ/include/ which is a link to a file planeras.h in nspr
And so i don't know, how to include these files anymore.
I always have trouble when it comes to include 3rd party header files.
Thanks
This is an old question, but I'll answer it anyway for future reference.
The simplest way is just to use the NSS package for your operating system.
Then you can use things like nss-config --cflags, nss-config --libs, nspr-config --cflags and nspr-config --libs and add that to your CFLAGS and LDFLAGS as appropriate.
For those who do decide to compile their own NSS, I'll give the quick overview.
The NSS headers are in dist/public. Add -I/path/to/dist/public to your compiler command line. The NSPR headers are in dist/Debug/include¹ so add -I/path/to/dist/Debug/include to your comiler command line.
Now you can use #include <nspr/prio.h> and #include <nss/nss.h> and friends.
The NSS code relies on directly uncluding the NSPR headers, so you'll need to add -I/path/to/dist/Debug/include/nspr for it to find things like plarena.h. Or you could do the same and not prefix your includes like I did above. It's up to you.
Now add -L/path/to/dist/Debug/lib and -lnss3 -lnspr4 to your linker command line. You may want to also add -rpath /path/to/dist/Debug/lib for the runtime link path, or copy them to a system directory or use LD_LIBRARY_PATH.
I hope this gets you started.
¹ This actually depends on your operating system and build type. I hope you can figure out the name of the actual Debug directory in your case.
Trying to run the following:
#include<iostream>
#include<boost/filesystem/operations.hpp>
namespace bfs=boost::filesystem;
int main()
{
bfs::path p("second.cpp");
if(bfs::exists(p))
std::cout<<p.leaf()<<std::endl;
}
I got some errors in cygwin so I decided to try out netbeans, and used the following as a guide. I added all links and the following for filesystem Project -> properties -> Linker ->Libraries -> Add option -> Other -> -lfile_system as noted here. I have run a separate test using #include<boost/any.hpp> so I am not currently doubting that my boost is not installed correclty.
It seems weird to me that it is "file_system", so I also tried "filesystem" but to no avail.
When i hold Ctrl and click on #include<boost/filesystem/operations.hpp> my netbeans brings up my operations.hpp file so it seems okay (linked properly internally that it can "see" what I want it to see).
The solution to installing boost came in the following form:
1 - If you have any path variables that are being used for Visual Studio you should temporarily change the variable during installation. This is a good guide. Once that is done, this is one step completed.
2 - Download and install MinGW. This is a very easy process and you can find the installer files here.
Once you have done these things (if you are in the same situation as me), you will now be able to properly install boost.
Horay!
Using Boost with cygwin step by step
Create a new Project
It is better to take the names given here in this tutorial exactly. Later ask: It does not work, can then be easier to find.
I do not think I need to mention all T:\ must of course be replaced with your drive.
Project Name : Boost-cyg-Test
Now your Project should look like
Open main.cpp
Overwrite the generated code with the following. We want to that, first of all everything works without error.
Therefore, please do not use your own special code.
It is difficult to find a fault. Then told after several ask, to get:
I have used my own code
#include <iostream>
#include <boost/filesystem.hpp>
using namespace std;
using namespace boost::filesystem;
int main()
{
path p("second.cpp");
if (exists(p)) { std::cout<<p.leaf()<<std::endl; }
}
In this section we assume that "boost" is already compiled.
goto Tools -> Options
Your C++ Code Assistance options should look something like this.
If this is not so, we should let Netbeans create that for us.
Add New Tool Collection
After we have completed this dialog with OK, we should find the settings shown above. ( C++ Code Assistance options).
Copy all libs into the right place
Let's create a new folder 'boost'.
With a search tool, search in your compiled Boost folder for *.a
My Boost is compiled with the shared option so we find :
For our short App. we need only 2 files.
libboost_filesystem-gcc45-mt-d-1_53.dll.a
libboost_system-gcc45-mt-d-1_53.dll.a
But if we're at it to copy two files, we can copy all files.
So mark all found .a files and copy them into the directory just created
T:\cygwin\lib\boost .
Now we do the same with our .dll files.
Mark all .dll files and copy it in your ?:\cygwin\bin directory.
If you only have compiled static librarys, you can skip this point.
Now it's time to modify our project settings.
As you can see i put my source Boost folder into cygwin
and
As we have already noted above, we need two .a files.
with Add Library navigate to T:\cygwin\lib\boost and select
libboost_filesystem-gcc45-mt-d-1_53.dll.a
libboost_system-gcc45-mt-d-1_53.dll.a
Now you'll notice that this name was shortened by netbeans to:
boost_filesystem-gcc45-mt-d-1_53.dll
boost_system-gcc45-mt-d-1_53.dll
This is somewhat confusing. It looks as if a .dll is standing here. But it is really a .a file.
Set a breakpoint in main.cpp. Now we start debug.
I have marked the important part, the two libs, with an arrow.
All libs are found and after make has finished, stops at the breakpoint.
The output:
Build Boost for Cygwin
For all who want to create boost with shared library itself.
Download boost_1_53_0.zip
Create a folder in your ?:\cygwin directory.
boost_1_53_0
Extract the zip file into that directory.
It should look like:
open a cmd window, cd to boost_1_53_0 directory.
To have a clean build we need a PATH that have only the cygwin home and bin.
In the cmd type.
SET PATH=T:\cygwin;T:\cygwin\bin
and test the path.
PATH
Type
bootstrap.bat
Type
.\b2 --build-dir=T:\boost-cyg toolset=gcc variant=debug link=shared runtime-link=shared
After some time the build is finished.
Now you have the same environment that we have used in the tutorial.
If you get a Error : gcc not found
copy (not rename) in ?:\cygwin\bin folder, for example : (names may differ).
i686-pc-cygwin-gcc-4.5.3.exe to gcc.exe
and
i686-pc-cygwin-g++-4.exe to g++.exe
Hope it helps you.
Could you paste the error you get when compiling ?
I am not used to compile programs in a Windows environment, but I think as Jesse Good suggested in a comment that you have a linker error.
You may solve it by using -lboost_filesystem instead of lfile_system.
To find out how your libs are called, you get the name of your lib (on my unix environment I have libboost_filesystem.so), strip the "lib" prefix and the ".so" or ".a" suffix (must be different in a Windows environment).
if your boost installation is correct and you are sure about it then for Unable to resolve identifier try Code Assistance->Reparse Project from context menu of the project. It tries to recover broken code model by reparsing project from scratch. if that didn't workout try closing IDE and removing code model cache.
p.s. do you have compilation errors?
i just installed YouCompleteMe for Vim through vundle. It works, but it shows only the words contained in the current file. I want to use it to develop c++ programs, how can i configure it to show autocompletion from c++ headers file in /usr/include for example? Thanks a lot.
You need to navigate to ~/.vim/bundles/YouCompleteMe and run the installation script with --clang-completer, so do ./install.sh --clang-completer. After it finishes you should have support for C like languages.
You may also need to place let g:ycm_global_ycm_extra_conf = '~/.vim/bundle/YouCompleteMe/cpp/ycm/.ycm_extra_conf.py' in your ~/.vimrc.
I have installed with pathogen. I tried the above instructions with ./install.sh --clang-complete. After this, it did not work, and I indeed had to add the path. But it was different than in another reply here, namely
let g:ycm_global_ycm_extra_conf = '.vim/bundle/YouCompleteMe/third_party/ycmd/cpp/ycm/.ycm_extra_conf.py'
so there is an extra "third_party/ycmd" in the path.
While the suggestions here might work in the beginning, I am not sure it's the proper way to go. According to YCM developer, whenever you start a project, you need a new .ycm_extra_conf.py file
From https://valloric.github.io/YouCompleteMe/#ubuntu-linux-x64-super-quick-installation
YCM looks for a .ycm_extra_conf.py file in the directory of the opened file or in any directory above it in the hierarchy (recursively); when the file is found, it is loaded (only once!) as a Python module. YCM calls a FlagsForFile method in that module which should provide it with the information necessary to compile the current file. You can also provide a path to a global .ycm_extra_conf.py file, which will be used as a fallback. To prevent the execution of malicious code from a file you didn't write YCM will ask you once per .ycm_extra_conf.py if it is safe to load. This can be disabled and you can white-/blacklist files. See the Options section for more details.
While you might only need to modify the compile flags from the vanilla .ycm_extra_conf.py, I feel it is advisable to create a new file for every project you start.
Everything that the folks here have said is correct. I just want to add that as of 2017, the "install.sh" script is deprecated. Now, you have to use the install.py script instead by typing
./install.py --clang-completer
Also, in your .vimrc file, instead of ".vim/bundle/blahblahblah", you'll need to add a "~/" in front of the address by adding:
let g:ycm_global_ycm_extra_conf = "~/.vim/bundle/YouCompleteMe/third_party/ycmd/cpp/ycm/.ycm_extra_conf.py"
to your .vimrc file, to give it an absolute path from the Home directory so that Vim can find the ".ycm_extra_conf.py" file. Otherwise, you might experience some funny behavior.
I just wanted to add if you don't want to manually define a config file there is this neat little repository that will auto generate it. https://github.com/rdnetto/YCM-Generator
I'm just getting my feet wet in C++ using the Stanford CS 106B lectures available online. The assignments have the students use some custom libraries which are available for download online, although the installation instructions are gone.
While I can do the assignments in Xcode using a pre-built blank project which includes the relevant files and source trees set up, I also have TextMate on hand and thought I'd like to try coding with it, since I liked using it a lot for coding LaTeX. So far so good.
The first program I'm trying to run (a very simple ten-line program) contains an # include "genlib.h" in the first line. I have the genlib.h file, but can't seem to get either of the following to work:
Add the path to the relevant file in TextMate: When I try to add the path to the folder on my desktop (/previouspathinthelist:/Users/me/Desktop/C++\ libraries) where the file lives I get an error: /Users/me/Documents/c++ programs/powertab.cpp:9:20: error: genlib.h: No such file or directory even though the file is right there! (Maybe I should note here that the file to be imported and the program file are in two different folders).
Add the file to one of the other paths: I can't move the files using mv in terminal to usr/bin, usr/sbin, etc. because it says I don't have the proper permissions.
Is there something I'm doing wrong in setting my path to my folder in Documents? There aren't any spelling mistakes or anything since the path came straight from get info in the finder. I know this is a programming forum and not a TextMate support forum, but I thought it'd be good to know where people generally put these kinds of files on their systems.
Just put the file in the same directory as your other source files.
#include "filename"
searches the source directory first, whereas
#include <filename>
only searches the include file path.
The reason why /previouspathinthelist:/Users/me/Desktop/C++\ libraries doesn't work probably has to do with the space in the file name. It is quite possible that a backslash is not the right way to quote the space in the tool you're using. Many tools from the C/unix tradition deal rather badly with pathnames that contain space (even though the Unix kernel itself has no such problem); often you'll find that there is no single amount of quoting that will simultaneously satisfy all the tools and subsystems that use some setting. Better to avoid spaces in filenames entirely when you're doing development.