hello.cpp First C++ program help?

[Lucifer666]

As you've probably guessed, I'm onto my very first "Hello World!" C++ program, which seems easy enough.

In Ubuntu, I've opened up the text editor and I've written the code and saved it as a .cpp which worked fine.

In the terminal, after taking it to the place where I saved my .cpp, I wrote:
g++ -Wall -W -Werror hello.cpp -o hello

It created a file in that folder, with no extension, which I guess is expected on Linux.

If I type "./hello" (without "s), it says Hello World! on my screen. Great.

Now the issue is that when I head over to the folder where hello is saved, double-clicking it won't do anything.
How can I change it in a way so that it won't need to be opened using the terminal, but rather simply by being double-clicked?

Thanks in advance, and I apologise for my noobiness. I guess we all start somewhere

 

[pistone]

if you are new to programing is a good thing to start with a text editor as you will remember things easy but somehow is not that simple if you want a nice coding editor for ubuntu try Geany as is a great ide
also if you want a better program try code::blocks
and then tell me

 

[hamstarr]

From the top of my head: easiest way to do this in Ubuntu,

create a shell script (echo "./hello" > run.sh) , make it executable (chmod +x ./run.sh)
double click the run.sh file, and Nautilus will ask what to do with the shell script (run, display in terminal, edit, etc)

note: when doubleclicking the ./hello executable from Ubuntu, it does actually run the executable, but because there is no GUI, no output is shown, because its not run in console mode/terminal.

The best fix is to actually instantiate a gui-window (for example with GTK), and output the text there.. see http://developer.gno...#SEC-HELLOWORLD

 

[Lucifer666]

From the top of my head: easiest way to do this in Ubuntu,

create a shell script (echo "./hello" > run.sh) , make it executable (chmod +x ./run.sh)
double click the run.sh file, and Nautilus will ask what to do with the shell script (run, display in terminal, edit, etc)

note: when doubleclicking the ./hello executable from Ubuntu, it does actually run the executable, but because there is no GUI, no output is shown, because its not run in console mode/terminal.

The best fix is to actually instantiate a gui-window (for example with GTK), and output the text there.. see http://developer.gno...#SEC-HELLOWORLD

Thanks! That worked
Also thanks for the explanation to why it won't run without the terminal. I wouldn't have figured it out myself.

 

[Lucifer666]

I've actually encountered another issue! I didn't want to make a new thread, so I'll post it here:

So I've written my very first extremely basic code in a file called Functions2.cpp

This is what it consists of:

#include 
int Add (int first, int second)
{
std::cout

 

[redfalcon]

Because thats exactly what you programmed. You type in two numbers, add them, print the solution and exit the program. If you want to leave the window open, you either need to pause the application, or wait for a final "return" keypress. Hint: You basically did the latter before.

 

[Lucifer666]

Because thats exactly what you programmed. You type in two numbers, add them, print the solution and exit the program. If you want to leave the window open, you either need to pause the application, or wait for a final "return" keypress. Hint: You basically did the latter before.

Thanks man, I added the two lines

char response;
std::cin >> response;

Before the return 0; bit and it worked.

Not too shabby for my first day!

 

[Lucifer666]

I've stumbled upon yet another obstacle in my C++ adventure. This time it isn't really a big thing hindering my C++ app development, but rather just a little misconception that's been bugging me for a while and some clarification would be appreciated.

So I've got my C++ textbook in front of me. I've pretty much finished working with enumerations and arrays and reached a section which basically recaps what I've been doing in the past couple chapters, and there's this note which really bothers me:

To declare an array, write the type of object stored, followed by the name of the array and a subscript with the number of objects to be held in the array.
Example 1
int MyIntegerArray[90];
Example 2
long * ArrayOfPointersToLongs[100];
To access members of the array, use the subscript operator.
Example 1
// assign ninth member of MyIntegerArray to theNinthInteger
int theNinthInteger = MyIntegerArray[8];
Example 2
// assign ninth member of ArrayOfPointersToLongs to pLong.
long * pLong = ArrayOfPointersToLongs[8];
Arrays count from zero. An array of n terms is numbered from 0 to n-1.

I know, very simple stuff.
The bits that are bothering me are those in bold.
This is the first time these have popped up in the whole book in that form (in the recap section too?), and I'm really unsure what they do.
So it says to specify the type of object when defining an array, that's fine. Except that 'long' isn't exactly a type of variable/object, it's just the amount of storage given to a variable (and this also depends on the compiler IIRC). That being said, the actual variable type hasn't been specified, and there's this star '*' right after it, whose function I am currently unsure of. Is 'long *' a fancy way of writing 'long int' ? If not, exactly what is long *? Thanks.

 

[megazig]

it means a pointer to a long.



edit:
long is a type that is the same as a long int: http://en.wikipedia.org/wiki/C_data_types
as the variable name says, it's an array of pointers to longs. the video should explain the pointer idea. and then it's just a list of those.

 

[Lucifer666]

-snip

That was incredibly helpful. Thank you for the clarification.