help passing arguments

[newdomingo]

¡Hola amigos!

i receive an error in the code:

#include <iostream>
#include <pthread.h>

using namespace std;

struct arg_struct {
    int arg1;
    int arg2;
};

void *print(void *arguments)
{
    struct arg_struct *args = arguments;
    cout << args -> arg1 << "\n";
    cout << args -> arg2 << "\n";
    pthread_exit(NULL);
    return NULL;
}

int main()
{
    pthread_t thr;
    struct arg_struct args;
    args.arg1 = 10;
    args.arg2 = 20;
	
    if (pthread_create(&thr, NULL, &print, (void *)&args) != 0) {
        cout << "\nERROR\n\n";
        return -1;
    }
	
    return pthread_join(thr, NULL);
}

the error is:

file.cpp: In function âvoid* print(void*)â:
file.cpp:14: error: invalid conversion from âvoid*â to âarg_struct*â

How can i solve it, please ?

[bramankp]

You don't need to cast from "any pointer" to "void pointer" but you need to cast from "void pointer" to "any pointer".

struct arg_struct *args = static_cast<struct arg_struct *>(arguments);

[bluecoder]

Hi ,
Have you tried

struct arg_struct *args = (arg_struct*)&arguments;

also make the changes like

int*  print(void *arguments)
{
    struct arg_struct *args = arguments;
    cout << args -> arg1 << "\n";
    cout << args -> arg2 << "\n";
    pthread_exit(NULL);
    return NULL;
}

I think this will work