Running sleep() function on g++

[vineeta7]

hi

I am using sleep() function for wait for 1 second.I tried it with gcc and its working properly.But when I used this sleep() function in c++ program and compile with following function then it is giving error as:

[vineeta@vineeta vineeta]$ g++ thread2.cpp -o thread -lpthread
thread2.cpp: In function `void* fun_count(void*)':
thread2.cpp:16: `sleep' undeclared (first use this function)
thread2.cpp:16: (Each undeclared identifier is reported only once for each
function it appears in.)

Why I am grtting this error????

Please reply

[Javasnob]

sleep is defined in stdlib.h. Correct me if I'm wrong, but gcc (and other C compilers) automatically includes certain headers like stdio and stdlib, whereas C++ compilers don't. Try adding #include<cstdlib> to the top of your program and see how that works out.

[vineeta7]

I tried but its not working.... where is error.These are my files


FILE 1 samspec.cpp

#include <stdio.h>
#include <cstdlib>
#include<pthread.h>
#include"./samspecCount.h"

int main()
{
Classcnt cnt;
cnt.createthread();
exit(0);
}

FILE 2 samspecCount.cpp

#include <stdio.h>
#include <pthread.h>
void *Counter_fun(void* ptr);

void Classcnt::createthread(void)
{
char *msg1="Count_thread";
/*Create thread which will execute function*/
retCntThread=pthread_create(&Count_thread,NULL,Cou nter_fun,(void*)msg1); pthread_join(Count_thread,NULL);

}

void* Counter_fun(void* ptr)
{
char *message;
int count,sum;
int maxcnt=20;
int i;
message=(char*)ptr;
printf("\n%s",message);
for(i=0;i<maxcnt;i++)
{ sleep(1);
sum+=count;
count++;
printf("%d %d",sum,count);
}
}

FILE 3 samspecCount.h

#include<pthread.h>
#include<cstdlib>
class Classcnt
{private:
pthread_t Count_thread;
int retCntThread;
public:
// Classcnt(void);
// ~Classcnt(void);
void createthread(void);
};


I have compiled it with following options:
#g++ samspec.cpp samspecCount.cpp -o samspec

Please help me

Vineeta7

[vineeta7]

I have added these two files in specspecCount.cpp also.

#include "./samspecCount.h"

#include<cstdlib>


Still getting following error:


g++ samspec.cpp samspecCount.cpp -o samspec
samspecCount.cpp: In function `void* Counter_fun(void*)':
samspecCount.cpp:26: `sleep' undeclared (first use this function)
samspecCount.cpp:26: (Each undeclared identifier is reported only once for each
function it appears in.)

[vineeta7]

hi
got the answer!!!

u need to add #include<unistd.h>