Dumb C question.

[PlanetaryAlchemy]

Hey all,

Apologies for the dumb question off the bat, I'm sure it's an easy answer. Trying to learn C, when I complete the program, save, chmod +x num.c, then try and run it, I get the error below.

./num.c: line 2: syntax error near unexpected token `('
./num.c: line 2: `int main()'

Am I getting this error as I haven't complied it first? Or is it a problem with how I've written the code?

Thanks

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#include <stdio.h>
int main()
{
        int Number1;    // 1
        int Number2;    // 3
        int Number3;    // 5

        Number1=13579   // 2
        Number2=2468    // 4

        sum=Number1+Number2;    //6
        printf("%d",sum);
        return 0;
}


[nathandelane]

So first off, C is a compiled language, not a scripting language. This means that in order to run the program you must compile it into an executable. .c files are not inherently executable. Try running this in the same directory as your program file:

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gcc -o num num.c


Then to execute the program just do

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./num


Before this will work completely though you will need to declare your sum variable at the top of your main function like:

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int sum;


[PlanetaryAlchemy]

You deserve a big slice of chocolate cake. Thanks for that!

[s0fa]

Just some sort of tips you may not know (if you knew them before, just ignore my posting):

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        int Number1;    // 1
        int Number2;    // 3
        int Number3;    // 5

You may declare variables of the same logical datatype in one line separated by commas. That would look like that in your case:

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int Number1, Number2, Numer3;

Just to make it clear what the gcc - command makes: gcc stands for "GNU Compiler Collection" and it has the following syntax:

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gcc parameters

gcc is - of course - the call of the function itself. You may open it with some parameters to influence the act of compiling. -o is such a parameter and it defines the name of the compiled file (without this parameter it would just be a.out). A list of possible parameters is available on the develeoper homepage or on different other pages through the net. The last point is the name of the input-data and the output, the compiled program.

Keep on learning!

[PlanetaryAlchemy]

Thanks for the advice s0fa.. I'm learning from http://www.learncpp.com. Any advice I can get will help I think.

[fabianhjr]

Hey in C if any function has no arguments because of the standard it would look something like this:

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int main(void)
{
    //etc
}


Just a tip.

[apples]

So first off, C is a compiled language, not a scripting language.

That's not true--C does not have to be compiled at all. The only restriction is that things must be executed according to C's abstract machine.

Hey in C if any function has no arguments because of the standard it would look something like this:<br>

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int main(void)<br>{<br>    //etc<br>}<br>

<br><br>Just a tip.

You forgot to include a return statement. Implicit returns are Not A Good Thing (TM). Also, an important distinction to make is that int main() { return 0; } is not the same thing as int main(void) { return 0; }.