Ofstream not writing to file C++

Question

I have this method which supposed to get a buffer and write some content to a file:

void writeTasksToDevice()
{

TaskInfo *task;
unsigned int i = lastTaskWritten;

printf("writing elihsa\n");
outputFile.write(" Elisha2", 7);
//pthread_mutex_lock(&fileMutex);

for(; i < (*writingTasks).size(); i++)
{
    task = (*writingTasks).at(i);
    if(NULL == task)
    {
        printf("ERROR!!! in writeTasksToDevice - there's a null task in taskQueue. By "
                " design that should NEVER happen\n");
        exit(-1);

    }
    if(true == task->wasItWritten)
    {
        //continue;
    }
    else // we've found a task to write!
    {

        printf("trying to write buffer to file\n");
        printf("buffer = %s, length = %d\n", task->buffer, task->length);<====PRINT HERE IS OK< PRINTING WHAT IS WANTED
        outputFile.write(task->buffer, task->length); <===SHOULD WRITE HERE
        printf("done writing file\n");
    }

}

//pthread_mutex_unlock(&fileMutex);


// TODO: check if we should go to sleep and wait for new tasks
// and then go to sleep




}

the buffer content is:

task->buffer: elishaefla

task->length: 10

i opened the stream in another init function using:

outputFile.open(fileName, ios :: app);
if(NULL == outputFile)
{
    //print error;
    return -1;
}

but at the end, the file content is empty, nothing is being written.

any idea why?

Solution

You did not provide enough information to answer the question with certainty, but here are some of the issues you might be facing:

1. You did not flush the buffer of the ofstream

2. You did not close the file that you are trying to open later on (if I'm correct, outputFile is a global variable, so it is not closed automatically until the end of the program)