When I create a new C++ project in netbeans,it prompts me to choose a name for the main file of the project
this is the file that gets executed when I press "Run" in the IDE
does anybody know how to change this file to another one AFTER I've already created the project?
You don't need to change the name or point to a different file.
In C++, on NetBeans or any other IDE, just place main function on a different file (the file you want to RUN when you press RUN on the IDE) and you should be done.
When we first time build and run a c project in netbeans- if there are more than one file with main() then it prompts us to select one of those files to be run. But after that it doesn't ask us to select a main file rather it uses the same file selected earlier, every time we run the program. So how to select other main file once we have selected one file during first attempt to run. I believe this is your question.
Answer: Right click project => select Properties => select make option under Build (in categories) =>Against Build result specify your file that you want to run. You can easily browse files with main() there. See picture-
Related
So I have a very specific question that I realize is a bit stupid, however regardless of how I search for it, nothing really shows up.
I am aware that I can use system() to execute commands in cmd, and I am so done with writing
g++ <filename.cpp> & a.exe & del a.exe
every time I want to compile, build and then delete the exe of a c++ app. Therefore I plan on making a simple handling software using c++ to open other c++ apps. It will just take the name of the app I am trying to run and do all of the things said in the above code. My problem is, when using cmd I can write the name of the file I am running, however how can I get the name of the file if I double click?
Example would be to always open cpp files with the program I am making. Upon double click, it will open a cmd console, type the code for me and execute the program. Then when I close the program, the cmd will close. I am aware how to do all of that, except how to get the file name of the file I am opening using the program.
I have tried using different libraries and have not found anything similar or at least nothing that states of this use. I am not expecting the whole program nor do I want it, I realize it is a simple project, however I am struggling with this one part and am unable to find a solution.
I simply want to make my own starting script. Then in file explorer I right click on any .cpp file, click open with and the dialog box shows up. I click the program I have created and there I compile the .cpp file with the script of my choice, however I do not understand how to get the path from right click, open with, and using my own program. This is all withing file explorer, not within the software I am making.
Using C++, if I launch an 'empty project', create a new C++ file, and try to run it, I just get this error message:
Unable to run program 'C:\Users\User\source\repos\Project2\Debug\Project2.exe' The system cannot find the file specified
I go to the file it's referencing and the file IS there -- what??
Using a 'Console App' project is different: it will actually compile and run the code.
Similarly, I can't join new header files to the main file, not even in a 'Console App' project: if I write the code for doing #include "Header.h", I get a red line underneath #include, and if I hover over that it says:
cannot open source file "Header.h"
I'm new to coding, and don't know why I'm having such a seemingly absurd problem here. Help!
You should create a new project and then create a c++ file. While adding a file, make sure to select c++ console application and do not check empty project if you are new.
From the result you described, I suspect you used File -> New file to add that cpp file, right? This does NOT add that file to a project.
Instead, you should right-click the Project file in the Solution explorer, select Add new item (or Project -> Add new item menu), and choose the C++ file type.
This works!
i know a lot of people asked this question, but i can't find how to do it. Is there
a way to build only one source file in visual studio 2017? without new project, i'm learning c++, so i can't make huge thing now, just focus to code(now i'm learn data structure and algorithm),most of my exercise is about <200 code lines, so it great to compile new file without whole project, sometimes i need a few lines of code to test my algorithm,please help me, thanks all you guy, because v.s is very good ide so i want to stick with it.
If you just have one file and want to build it without waiting 1-2 minutes for the IDE to pop up,
Find the Developer Command Prompt in your list of applications - it is under the Visual Studio directory in the Application menu.
cd /d to your directory. cd will take you here if you are on the same drive as visual studio. If you are on a different drive, use cd /d.
Use your favourite editor (notepad, vim, geany, notepad++, nano, microemacs etc) to create the file.
cl sourcefile
Run the excutable.
Unlike what visual studio does, you executable will now be in the same directory as your source. Editors like geany have a build button (the brick icon). All you need to do is fill in how to build: in this case, the cl command.
If you want a one file project, just follow these steps.
Create New Project - File -> New -> Project
Fill in filename, select Win32 Console Application. Note the directory - if it is not where you want it, change it. Click OK
Application Wizard pops up, click Next
Application settings - select Empty project, click Finish
Open Solution Explorer. Right click Source Files. Menu pops up, select Add -> New Item
Add new item dialog pops up, fill in your filename.
If you don't know how to create a new project and a new solution, it will be good to learn those basic concepts and use them to write, test, and debug your code.
You can use one Visual Studio project to do all the learning.
Let's say you want to test "algorithm 1". Then,
Create a header file for it and a source file for it -- call them "test-algorithm-1.hpp" and "test-algorithm-1.cpp".
Add them to the project.
#include the header file in the main .cpp file of the project.
Call the function to test "algorithm 1" from main.
#include "test-algorithm-1.hpp"
int main()
{
test_algorithm_1();
}
When you are ready for testing "algorithm 2", repeat the above steps. The main .cpp file can now be.
#include "test-algorithm-1.hpp"
#include "test-algorithm-2.hpp"
int main()
{
test_algorithm_1();
test_algorithm_2();
}
If you want to avoid testing "algorithm 1" while testing "algorithm 2", simply comment out the corresponding line in main.
int main()
{
// test_algorithm_1();
test_algorithm_2();
}
On the source file you don't want to be included in the project, simply right click, select Properties. There you will find in General a field 'Excluded From Build'. Type true/yes there and the source file will be deactivated.
I've been using windows in a class I've been taking but I am trying to run a basic code to figure out how to open/close/input/output from files on Xcode and the code I usually use on visual studios isn't working any idea why? thanks!
#include <string>
#include <iostream>
#include <fstream>
using namespace std;
int main()
{
ifstream fin;
ofstream fout;
string input;
fin.open("inputFile.txt");
if(fin.fail())
cout << "File failed to open." << endl;
fin >> input;
fout.open("outputFile.txt");
fout << input;
}
Put your .txt files in the same directory where your main.cpp file is (or anywhere you like).
In Xcode go to Product > Scheme > Edit Scheme > Run (on the left) > Options (middle top)
Down under Options for "Working Directory" check “Use custom working directory” and set it to the directory where you .txt files are located.
To work with the files, you will have to specify just file names, e.g. in_file.open("inputFile.txt"); no path is necessary.
Here's a completely different approach: Have Xcode copy the input file for you.
Select your project in Xcode
Select Build Phases
Click the '+' button to create a new Build Phase
Select New Copy Files Build Phase
Select Products Directory
Click the '+' button to add your file
Click Add Other
Select your input file and click Open
Check the Copy items… checkbox and click Finish
Now every time you build your project, the input file will be copied to the same folder as the executable no matter where it is built. Of course, to see the output file, you'll still need to find the executable in Finder.
The answers don't really explain the problem so I thought I'd do that.
When you pass a relative path like "inputFile.txt" to file APIs, it's treated as relative to the working directory when the program is executed. This is the same as the 'working directory' when you use cmd.exe or Terminal.app or command lines in general. The Unix command pwd ("print working directory") displays the current working directory. On Windows running the command cd with no arguments performs the same function. (On Unix running cd with no arguments will change the working directory to the user's home directory.)
When you run a program from the command line, the command line shell sets the program's working directory. When you run a program from within an IDE, the IDE sets the working directory. Since, unlike on a command line, there's no obvious answer for what the IDE should set as the working directory, Visual Studio and Xcode set the working directory to different locations by default: Visual Studio sets the working directory to $(ProjectDir), the directory containing the Visual Studio project file; Xcode sets the working directory to the build products directory, i.e. the location the executable was written to.
Some possible solutions to your problem are:
Do not use a relative path, and therefore don't depend on the working directory. This isn't much help in making the program more portable, because the absolute paths will also differ between platforms, and so you will still have to 'configure' the program for each platform. In fact using an absolute path is worse, because it means your source code must differ, whereas it would be better to keep that difference confined to each platform's build configuration.
Configure the IDE to use your desired working directory. Visual Studio can be configured by right clicking the project, selecting Configuration Properties > Debugging > Working Directory, and setting the working directory to the desired path (potentially using Visual Studio build variables).
nepete's answer describes how to configure the working directly set by Xcode.
Configure the IDE's build process to copy your data files to an appropriate location. In Visual Studio you would do this in a C++ project by configuring the project's Properties > Configuration Properties > Build Events.
SSteve's answer covers how to configure additional build steps in Xcode.
I'm guessing you have inputFile.txt in the folder that contains your source code. That's not going to work. You need to put it in the folder that contains the generated executable. To find that folder, right-click on your app under Products and select Show In Finder.
This image shows what it looks like for a command line program. It also shows the Finder window that was opened. As you can see, it is a different folder than the one containing the source code.
As suggested by nepete, edit the scheme, but use $PROJECT_DIR as the custom working directory. Helps with moving the project around, or working in two different environments (e.g., home and office).
BTW. $PROJECT_DIR is one of the Xcode Environment Variables, and also helps with passing file names as command line arguments to programs (settable under "Arguments" in the scheme).
I've struggled with the same problem today. I wanted to add C code to my Swift project and my file pointer was always NULL.
Unfortunately, in XCode 9 for iOS app, I couldn't change the working directory. Changing Build phases didn't help me either. After 4+ hours of trial and error, that's what I've come up with finally and it works:
when copying files to XCode, I've chosen "Create groups", but I needed to choose "Create folder references":
I created a new objective-c file (.m) and copied all my C code there.
I left untouched .h files (XCode generated bridging header and my own .h file with public functions declaration). Now my project structure looked like this:
In my dict.m file in place of previous plain c fopen part:
FILE *dic = fopen("dictionary.txt", "r");
I added obj-C code:
NSString *filePath = [[NSBundle mainBundle] pathForResource:#"dictionary" ofType:#"txt"];
FILE *dic = fopen([filePath cStringUsingEncoding: NSUTF8StringEncoding], "r");
And it works now without any problem! It's just amazing!
ps I decided to write this answer in case it will help someone like me and will save them some time. If you know how to change working directory in XCode 9 for iOS, please, leave me a comment - now I am really curious why I can't find it.
I am new to c++ and am making a very simple program. All my program does is call a function from the main function, which reads in a text file and returns. To check that I am reading in the file correctly, I am trying to print out the strings I have read in. The print out (cout) works properly when I run from Visual Studio (f5). However, when I run the executable from command line, none of the print outs from my function show up. Only print outs directly in the main function appear. I cannot find a similar question elsewhere. Any help would be appreciated.
When you run a program from within VC++ the current directory is set to the project directory by default, but the application is by default in a different folder.
E.g. the application may be:
D:\Work\MyApp\Debug\MyApp.exe
But the project directory may be:
D:\Work\MyApp\MyApp\
When you start the program from outside of VC++ you need to take steps to make sure the current directory is correct, or that the executable and any data files it refers to are in the same folder.
The default working directory for an IDE-launched project in Visual Studio is the project folder. This is the folder where you project file resides (the .vcproj or .vcprojx file is the project file).
If the data file you are reading is in the same folder, code like this:
std::ifstream inf("datafile.txt");
will succeed because the current working folder and the folder where the data file resides are the same.
However, if you switch to where the executable was written (typically this is the project-dir/Debug or project-dir/Release folders) and run the same executable from a command-shell, the data file will not be found.
To test this is the case. Do the following:
Open a command prompt.
Switch to the project folder where your data file resides.
Run the executable with a specified path: ./Debug/YourProgram.exe, for example.
Note: you can avoid this by having the program take the data file name as an argv[] parameter. Then your program will simply use whatever file you tell it to at launch-time.