I'm extremely confused over how to make in c++. I'm working on a school project where we downloaded several files -- some starter code, and some libraries. File structure is something along the lines of
main --- lib/ severalLibraryFolders
\--- src/ starterCode
I cannot seem to get the starter code to make within the command line. There's a vector library within one of the library folders and when I run make on the starter file (a .cpp and .h) I get a fatal error: 'vector.h' not found. I managed to use gcc and the -I flag to include the folder that vector.h was in which fixed it -- however other similar problems popped up even after I used the -I flag on all possible library folders.
I'm fairly certain I'm doing something wrong/need a makefile but all the examples I've found are not clear on how to do what I need to do, which is essentially to find all header files below the parent directory. I'd love some direction here, as I come from a more scripty background where this sort of thing is much easier!
I'm ashamed for not being able to solve this but i can't make this work. I have this brief test:
std::string archnom = "../data/uniform.txt";
ifstream archin(archnom.c_str());
ASSERT(archin.good());
The assert is throwing error. For some reason it's not locating the uniform.txt file. The project structure is:
project
---> data/uniform.txt
---> a.out
---> main.txt
I've already tried changing archnom as follows without success:
std::string archnom = "/data/uniform.txt";
std::string archnom = "./data/uniform.txt";
std::string archnom = "../data/uniform.txt";
std::string archnom = "data/uniform.txt";
What is the problem here?
In a terminal, you can type ./build/a.out to launch the a.out program with ./ as the current working directory.
When you do this, relative filepaths that are used in your program are relative to the ./ dir -- not the one which contains the program.
For example, if I want to open ex.txt when running ./build/a.out (and ex.txt is in the same directory as build), my program should have the relative path ./ex.txt - not ../ex.txt.
std::string archnom = "../data/uniform.txt";
Tells the program that uniform.txt can be found by going back one directory and then up into data.
But in what directory does the program start looking? Good question. That location is called the Working Directory, and unfortunately it MOVES. Typically the working directory starts as the directory the program is run from, not where the program is. For added excitement your program can change the working directory while running.
So if your program is at /home/bob/code and the uniform.txt file is at /home/bob/data and you run the program from /home/bob/code with ./program all is good. The working directory is /home/bob/code and the program goes back one folder and then up into data.
What if you were in /home/bob/workspace and you ran ../code/program. The working directory is /home/bob/workspace and the program goes back one folder and into data.
But what if you run the program from / with /home/bob/code/program? The working directory is /. You can't really go back anywhere, can you?
Let's try a less extreme case: /etc. Program goes back to / and forward to... rats. No data directory.
If the uniform.txt file is always going to be in the same place and this place is guaranteed, use a fixed path. If uniform.txt is going to be somewhere near the installation directory of the program, your program needs to know where it is and that takes OS specific code.
You need to make sure the current working directory is where you expect it to be. You can do that by using _chdir (win32) or chdir (gcc) and by using argv[0] (which contains the path to the currently running executable).
I showed how to do this in my answer to another question here :
Change the current working directory in C++
Suppose that I add a program to path that is dependent on a file name "test.in". I programmed this in C++ so I used ifstream fin("test.in") without specifying the directory. Now if I were to run this program from a different directory, would the program be able to access the file "test.in"?
Firstly, this has nothing to do with the file extension, which is merely a convention given as part of the filename.
Secondly, you were always using a relative path. Even when you were running your program "from the same directory" as test.in, you were reliant on the "working directory" of your shell context being the same as the directory in which the executable and the file reside.
This is not always the case.
For example:
~/myProject:# ls
test.in
program
~/myProject:# ./program
This is okay, because your shell is at ~/myProject, and so is test.in.
However, if you'd written:
~/myProject:# cd ..
~:# ./myProject/program
…then your test.in file wouldn't be found, as it does not exist in ~. It exists in ~/myProject. It doesn't matter that the executable itself is also found in ~/myProject.
This is actually desirable behaviour, as it allows flexibility from the shell. Ideally you would allow support for piping/redirecting the file to the process instead (program < test.in — now there are no assumptions baked into your code at all!), but we can save that for another day.
For now, you seem to be concerned about what happens if you move the executable away. Don't worry: just use this feature!
~:# mv myProject/program .
~:# cd myProject
~/myProject:# ../myProject
Your working directory is the directory in which test.in resides, so it will be found via the relative path given in your program code.
I'm trying to figure out where to save multiple .txt files so that i can have a command line tool project in Xcode read directly in from them while running it.
I understand that Xcode compiles everything to a folder, DerivedData, which i have saved in the same location as my source code for each project respectively.
can i save multiple .txt files anywhere in the DerivedData folder or include it in the build settings and phases so that when i run the command line tool i can type the name of a file, it will read in from that file.
By default the compiled/linked binary will look into its own directory for files.
For example, my binaries are at ProjectName/Build/Products/Debug/ and therefore it will look for files from that dir.
You can use relative path from that folder to the outside.
Or, you can create a symbolic link to another directory (on Terminal):
ln -s source_dir target_file
target_file must be located in the same directory as your binary. And you can reference the other files like "target_file/file1.txt", etc.
I know that you are supposed to place any external libraries under the "libraries" folder of the arduino install directory, but I have a project that uses several libraries that I have created for the project and mainly to keep all that code self contained and out of the main pde file. However, I have tried to place the libraries in the same directory as the main PDE file so that I can more easily keep everything synced up in subversion (I work on this on multiple computers) and I don't want to have to keep going back and syncing up the libraries separately. Also, just for the sake of being able to easily zip of the sketch folder and know that it contains everything it needs.
I've tried adding the header files to the sketch as a new tab, but that doesn't seem to work at all... don't even care if they should up in the arduino IDE.
I've also tried adding the libraries to the sketch directory in subdirectories (what I would greatly prefer) and then linking to them as:
#include "mylib/mylib.h"
and
#include <mylib/mylib.h>
But both of these result in file not found errors.
Is this possible? And, if so, how do I include them in the main file for building? Preferably in their own subdirectories.
I had the same issue. Solved it for Arduino IDE > 1.8. Seems a specialty in newer IDEs (?) according to the reference (see bottom link).
You have to add a "src" Subdirectory before creating a library folder. So essentially your project should look like this:
/SketchDir (with *.ino file)
/SketchDir/src
/SketchDir/src/yourLib (with .h and .cpp file)
and finally in your sketch you reference:
#include "src/yourLib/yourLib.h"
otherwise in my case - if I am missing the "src" folder - I get the error message that it cannot find the yourLib.cpp file.
Note: I am using a windows system in case it differs and actually VS Code as wrapper for Arduino IDE. But both IDE compile it with this structure.
References:
https://forum.arduino.cc/index.php?topic=445230.0
For the sketches I have, the "*.h" and "*.cpp" library files actually reside in the same folder as the sketch, and I call them like "someheader.h". I also noticed that if I go into sketch menu and add file... that the file doesn't appear until I close and reopen the sketch.
I agree with you; this is an intolerable way to develop software: it requires every file that you need to be in the same directory as the main program!
To get around this, I use make to put together a single .h file from my .h and .cpp sources - you can see this used in this Makefile:
PREPROCESS=gcc -E -C -x c -iquote ./src
# -E : Stop after preprocessing.
# -C : Don't discard comments.
# -x c : Treat the file as C code.
# -iquote ./src : Use ./src for the non-system include path.
TARGETS=sketches/morse/morse.h
all: $(TARGETS)
clean:
rm $(TARGETS)
%.h: %.h.in
$(PREPROCESS) $< -o $#
Arduino is very picky about file endings - if you put a .cpp or .cc file in its directory it automatically uses it in the source, and you can't include anything that's not a .cpp, .cc or .h - so this is about the only way to do it.
I use a similar trick also to put together JavaScript files here.
This requires that you run make after editing your files, but since I'm using an external editor (Emacs) anyway, this is zero hassle for me.
Unfortunately the Arduino IDE is awful and shows no signs of improving. There is no real build system so it only lets you build programs that reside in a single directory.
The only real solution is to write a makefile, then you can use a real IDE. I'm hopeful that one day someone will write an Arduino plugin for QtCreator.
Here's an example makefile:
http://volker.top.geek.nz/arduino/Makefile-Arduino-v1.8
I just had this same problem (I also like to keep the code self-contained), so I'll just jot down some notes; say I have a MyPdeSketch.pde using MyLibClass.cpp; then I have it organized like this
/path/to/skdir/MyPdeSketch/MyPdeSketch.pde
/path/to/skdir/MyPdeSketch/MyLibClass/MyLibClass.cpp
/path/to/skdir/MyPdeSketch/MyLibClass/MyLibClass.h
(In principle, /path/to/skdir/ here is equivalent to ~/sketchbook/)
What worked for me is something like:
mkdir /path/to/arduino-0022/libraries/MyLibClass
ln -s /path/to/skdir/MyPdeSketch/MyLibClass/MyLibClass.* /path/to/arduino-0022/libraries/MyLibClass/
After restart of the IDE, MyLibClass should show under ''Sketch/Import Library''.
Note that the only way I can see so far for a library class file to refer to other library files is to include them relatively (from 'current location'), assuming they are all in the same main arduino-0022/libraries folder (possibly related Stack Overflow question: Is it possible to include a library from another library using the Arduino IDE?).
Otherwise, it should also be possible to symlink the MyLibClass directory directly into arduino-0022/libraries (instead of manually making a directory, and then symlinking the files). For the same reason, symlinking to the alternate location ~/sketchbook/libraries could also be problematic.
Finally, a possibly better organization could be:
/path/to/skdir/MyLibClass/MyLibClass.cpp
/path/to/skdir/MyLibClass/MyLibClass.h
/path/to/skdir/MyLibClass/MyPdeSketch/MyPdeSketch.pde
... which, after symlinking to libraries, would force MyPdeSketch to show under the examples for the MyLibClass library in Arduino IDE (however, it may not be applicable if you want to self-contain multiple class folders under a single directory).
EDIT: or just use a Makefile - which would work directly with avr-gcc, bypassing the Arduino IDE (in which case, the sketchbook file organization can be somewhat loosened)..
Think I know what do u need exactly.
you have a project folder say MYPROJ_FOLDER and you want to include a Libraries folder that contains more children folders for your custom libraries.
you need to do the following:
1- create folders as follows:
-MyProjFolder
-MyProjFolder/MyProjFolder
and then create a file with the folder name in .ino extension
-MyProjFolder/MyProjFolder/MyProjFolder.ino
2- create libraries folder:
-MyProjFolder/libraries <<<<< name is not an option should be called like that.
3- then create your own libraries
-MyProjFolder/libraries/lib1
-MyProjFolder/libraries/lib1/lib1.cpp
-MyProjFolder/libraries/lib1/examples <<<< this is a folder
-MyProjFolder/libraries/lib1/examples/example1
repeat step 3 as much as you want
also check http://arduino.cc/en/Guide/Libraries
I did it a little differently. Here is my setup.
Visually this is the directory layout
~/Arduino/Testy_app/ <- sketch dir
/Testy_app.ino <- has a #include "foo.h"
/foo <- a git repo
/foo/foo.h
/foo/foo.cpp
Here is how I build:
~/Arduino/Testy_App/$ arduino-cli compile --library "/home/davis/Arduino/Testy_app/foo/" --fqbn arduino:samd:mkrwan1310 Testy_app
If you wish to be more elaborate and specify libs and src dirs, this also works
~/Arduino/Testy_app/ <- sketch dir
/Testy_app.ino <- has a #include "foo.h"
/lib <- a git repo
/lib/foo/src/foo.h
/lib/foo/src/foo.cpp
and the build method is:
~/Arduino/Testy_App/$ arduino-cli compile --library "/home/davis/Arduino/Testy_app/lib/foo/src" --fqbn arduino:samd:mkrwan1310 Testy_app
One more bit of tweaking needs to be done to include files from the lib dirs to main dir. If you need to do that, this is the work around:
~/Arduino/Testy_app/ <- sketch dir
/Testy_app.ino <- has a #include
"foo.h"
/inc/Testy_app.h
/foo <- a git repo
/foo/foo.h
/foo/foo.cpp < has a "include testy_app.h"
Then do the compile like this
~/Arduino/Testy_App/$ arduino-cli compile \
--library "/home/davis/Arduino/Testy_app/inc" \
--library "/home/davis/Arduino/Testy_app/foo/src" \
--fqbn arduino:samd:mkrwan1310 Testy_app
What has worked for me is to create a dir, for example "src" under the sketch dir, and under that a dir for each personal library.
Example:
I have a project called ObstacleRobot, under that a folder for my sketch, named obstaclerobot (automatically created by the IDE) and there my sketch "obstacleRobot.ino"
Up to now we have:
/ObstacleRobot
/obstaclerobot
obstacleRobot.ino
Then I wanted to include a personal library that was fully related with this project and made no sense in including it in the IDE libraries, well in fact I want to do this for each part of the robot but I'm still working on it.
What in the end worked for me was:
/ObstacleRobot
/obstaclerobot
obstacleRobot.ino
/src
/Sonar
Sonar.h
Sonar.cpp
Then what you have to do in the main sketch is to write the include as follows:
#include "src/Sonar/Sonar.h"
And thats all.
Following the lines of Hefny, make your project an example for your library.
For example (Unix env), let's say the libraries are in ~arduino/libraries
Your create your project ~arduino/libraries/MyProject, your libraries go there (for example ~/arduino/libraries/MyProject/module1.h ~/arduino/libraries/MyProject/module1.cpp ~/arduino/libraries/MyProject/module2.h ~/arduino/libraries/MyProject/module2.cpp
Now:
mkdir -p ~arduino/libraries/MyProject/examples/myproj
edit ~arduino/libraries/MyProject/examples/myproj/myproj.ino
(note that this is not examples/myproj.ino but examples/myproj/myproj.ino)
Restart the IDE, you should find your project in the menu File/Example/MyProject.
Also note that you do the include with #include
Why dont we just write a script with a single copy command, copying our libs from wherever our library is located into the arduino IDE library folder?
This way we keep the file structure we want and use the IDE library requirements without fuss.
Something like this works for me:
cp -r mylibs/* ~/Documents/programs/arduino-1.5.8/libraries/.
Note that the paths are relative to my own file structure.
Hope this helps someone. This includes my future self that I bet will be reading this in a near future... as usual!
J