Boost threads

Curiosity got the better of me when I had a few minutes to spare on the weekend and I thought I'd see what cool stuff boost threads was capable of. There are not many examples out there, but I found a couple and created something simple of my own as a result.

But I want to see it do something more interesting....let's say I've got a long log file I want to read into a vector for text analysis or whatever.

Is it possible to use threads either for the actual "getline" process (e.g. two threads, one processing odd numbered lines and one processing even) ? Or just "handing over" the output from "getline" to a thread or two ?

Any examples would be much appreciated !

For those that don't kow me yet in the C zone.... not homework, not work work .... just a plain curious C++ newbie.... ;-)

while (!is.eof()) {
		std::getline(is, lineString, lEnd);
		if (!lineString.length())
			continue;
// do stuff
}

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If you want to go for threads, you should use a problem that can be parallelized in a nice way, and I'm not sure whether line-by-line file reading necessarily is one, but anyway, that could be like the following (adapted from http://www.highscore.de/cpp/boost/multithreading.html)

#include <boost/thread.hpp> 
#include <iostream> 
#include <vector> 
#include <string>
#include <cstdlib> 
#include <ctime> 
 
boost::mutex mutex; 
boost::condition_variable_any cond; 
std::vector<std::string> lines; 
 
void fill() 
{ 
  std::ifstream is("test.dat");
 
  while (!is.eof()) {
     
    std::getline(is, lineString, lEnd);
    if (lineString.length()) {
 
      boost::unique_lock<boost::mutex> lock(mutex);
      lines.push_back(lineString); 
    }
  }
} 
 
void print() 
{ 
  std::size_t next_size = 1; 
  for (int i = 0; i < 3; ++i) 
  { 
    boost::unique_lock<boost::mutex> lock(mutex); 
    while (lines.size() != next_size) 
      cond.wait(mutex); 
    std::cout << lines.back() << std::endl; 
    ++next_size; 
    cond.notify_all(); 
  } 
} 
 
int main() 
{ 
  boost::thread t1(fill); 
  boost::thread t2(print); 
  t1.join(); 
  t2.join(); 
 
  return 0;
}

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