Using Threadpool in for loop

[GATTACA]

I have created this example program to teach myself how to use the ThreadPool and Runnable classes in POCO but I'm not having much luck.

Can someone tell me why this doesn't compile?
Thanks in advance for any and all help.

Code: Select all

#include <iostream>
#include <deque>
#include "Poco/Runnable.h"
#include "Poco/ThreadPool.h"

using namespace std;


class Task : public Poco::Runnable {
private:
   int _id;
public:
   Task() {};
   void setId(int x) { _id = x; }

   void run(){
      for (int i= 0; i < 100; i++){
         cout << i << ") Task " << _id << " is working" << std::endl;
      }
   }
};
   
int main(){

   Task *ptr = NULL;
   deque<Task> DT;
   deque<Task>::iterator iter;
   Poco::ThreadPool pool;
   
   for(int i = 0; i < 10; i++) {
      ptr = new Task();
      ptr->setId(i);
      
      DT.push_back(*ptr);
      delete(ptr);
      ptr = NULL;
   }
   
   for(iter = DT.begin(); iter != DT.end(); iter++) pool.start(*iter);

   pool.joinAll();   
   return 0;
}


Here is the compile error I get:

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$ g++ -O2 -Wall -static  -I./poco.lib/include -L./poco.lib/lib -lPocoFoundation learnPoco.cpp -o learnPoco.exe
/tmp/ccKMn21d.o: In function `main':
learnPoco.cpp:(.text+0xe3): undefined reference to `Poco::ThreadPool::ThreadPool(int, int, int, int)'
learnPoco.cpp:(.text+0x143): undefined reference to `Poco::Runnable::Runnable()'
learnPoco.cpp:(.text+0x231): undefined reference to `Poco::ThreadPool::start(Poco::Runnable&)'
learnPoco.cpp:(.text+0x25b): undefined reference to `Poco::ThreadPool::joinAll()'
learnPoco.cpp:(.text+0x263): undefined reference to `Poco::ThreadPool::~ThreadPool()'
learnPoco.cpp:(.text+0x389): undefined reference to `Poco::ThreadPool::~ThreadPool()'
/tmp/ccKMn21d.o: In function `Task::~Task()':
learnPoco.cpp:(.text._ZN4TaskD2Ev[_ZN4TaskD5Ev]+0x8): undefined reference to `Poco::Runnable::~Runnable()'
/tmp/ccKMn21d.o: In function `Task::~Task()':
learnPoco.cpp:(.text._ZN4TaskD0Ev[_ZN4TaskD5Ev]+0xc): undefined reference to `Poco::Runnable::~Runnable()'
/tmp/ccKMn21d.o:(.rodata._ZTI4Task[typeinfo for Task]+0x10): undefined reference to `typeinfo for Poco::Runnable'
collect2: ld returned 1 exit status


I'm sorry if this is a newbie question but I'm pulling my hair out trying to figure this one out.
The tutorials all suggest that I haven't made a mistake (or at least not one I can see).
I seem to have to define a constructor and destructor for both ThreadPool and Runnable??

[alex]

There's nothing wrong with the compilation of your code. There are two problems with linking:

1) order in which you specify files on the command line
2) since you are building static, you'll have to link with pthread as well

Try this:

Code: Select all

$ g++ -O2 -Wall -static  -I./poco.lib/include -L./poco.lib/lib learnPoco.cpp -o learnPoco.exe -lPocoFoundation -lpthread

[GATTACA]

Thanks alex.

The program works now!!!

I would never have thought that was the issue.