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Writing a "task main()" 
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vnguyen
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Post Writing a "task main()"
Tip: When using task main(), you only have to type it once!

Be very careful with using the correct characters such as parenthesis "()", and curly braces "{}".

The proper format should be:

Code:
task main()
{

}

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Tue Mar 18, 2008 10:21 am
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Dad and Adam
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Location: Plymouth, Indiana, USA
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Hello,
Slowly I've been learning C and RobotC. I just noticed some of the sample RobotC programs have "task main ()" at the beginning and some don't have "task main () at all. I just tried my own simple program and it didn't seem to matter if I used "task main ()" or not.
What is the criteria for when "task main ()" must be used? How can it sometimes not be needed?

For example: The RobotC sample programs; "NXT Hello World", "Execution Speed Test", and "NXT Hello World Expanded" don't have the "task main()". They are 12, 496, and 33 lines of code respectively.

Thanks.

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Dad (Dave) and Adam
Thu Apr 17, 2008 6:12 am
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Jetro
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Joined: Sat Oct 25, 2008 3:47 pm
Posts: 38
Post Re: Writing a "task main()"
I'm probably not the best person to try and answer your question seeing I'm a total noob at this, but I seem to remember that if a program has a "task main()" that task will be the first to be executed, no matter where it is located in the program. If it doesn't have a "task main()", the first task the compiler finds (reading from top to bottom) will be the first one to be executed.

Can anyone please confirm if I'm right?
Sat Oct 25, 2008 6:57 pm
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CC335
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Post Re: Writing a "task main()"
A task main() is normally the first function, in this case a task, that the compiler reads. If there is no task main, it reads form top to bottom. I also program in C++, and with C++ you use int main(), with the parameters in the parentheses if used. RobotC thus looks like this:
Code:
#include "JoystickDrivers.c"

task main()
{
    while(true)
    {
        getJoystickSettings(joystick);
        if(joy1Btn(1))
        {
            PlaySound(soundbeepbeep);
        }
    }
}

while C++ looks like this:
Code:
#include <iostream>
#include <string>

using namespace std;

string password;

int main()
{
    while(password != "admin")
    {
                   cout << "enter password" << endl;
                   cin >> password;
                   if(password == "admin")
                   {
                               cout << "Access Granted" << endl;
                   }
                   else
                   {
                       cout << "Access Denied" << endl;
                       cout << "Password Hint: Strongest" << endl;
                   }
    }
    system("PAUSE");
    return 0;
}

Either way, the * main(parameters if used) is the first function to be read.

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Sun Oct 26, 2008 5:35 pm
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mightor
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Post Re: Writing a "task main()"
I think the examples without the task main() that are shipped with RobotC are really counter intuitive and terrible examples of how to program RobotC. It sets a bad precedent. I think it would be good to rewrite them with a task main().

Xander

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Sun Oct 26, 2008 6:42 pm
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jagadeeshstel
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Joined: Sat Jul 30, 2011 10:03 am
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Post Operating system in NXT brick
which kind of operating system in NXT brick ?
what is RobotC (its application or operating system to NXT brick)
Tue Sep 06, 2011 2:27 pm
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mightor
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Post Re: Writing a "task main()"
It's not really a full operating system but a small firmware. ROBOTC is both the programming language -and- the programming environment.

- Xander

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Tue Sep 06, 2011 2:34 pm
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