Pthread_create Pass Parameters

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

using namespace Std;

pthread_t thread;

void *fn (void *arg)
{
int i = * (int *) arg;
cout<< "i =" <<i<<endl;

return ((void *) 0);
}

int main ()
{
int err1;
int i=10;

ERR1 = Pthread_create (&thread, NULL, &FN, &i);
Pthread_join (thread, NULL);

}

————————————————————————————————

Thread creation function:
int Pthread_create (pthread_t *tid, const pthread_attr_t *attr, void * (*FUNC) (void *), void *arg);
The parameter func represents one parameter void *, and the return value is void *;
For void *arg, parameters are passed in, and in the case of GCC 3.2.2, the following two ways can be passed in.
int ssock;
int tcpechod (int fd);
1.pthread_create (&th, &ta, (void * (*) (void *)) Tcpechod, (void *) ssock);
2.pthread_create (&th, &ta, (void * (*) (void *)) &tcpechod, (void *) &ssock);


This article from the Chinaunix blog, if you view the original please point:http://blog.chinaunix.net/u/9643/showart_49987.html

Pthread_create (&tid,&attr,&func, (void) arg) can only pass one argument to the Func, if you want to pass more than one parameter. define a structure and pass this structure .

can pass multiple parameters to the thread_function when Pthread_create. Code:typedef Union {
size_t arg_cnt;
Any_possible_arg_types;
} Arg_type;

Arg_type Args[arg_num + 1];
args[0].arg_cnt = Arg_num;
Args[1].xxx = ...;

Pthread_create (..., thread_function, &args[0]);

Go inside and parse it yourself.

------------------------- The use of pthread_create transfer parameters

Recently, the program that started to write the socket again. The
has a fork mode other than the previous use of Select or the earliest heavy-weight.
this time using pthread to handle the request received on the server side.
However, there is a problem, how to pass parameters to thread's handler
Man pthread_create can see only 4th argument can be applied.
How to use it. Looking for the previous sample code, the original, do casting can. The

string is not a problem, and if it is an integer, write it.

void Pfunc (void *data)
{
int i = (int) data;
...
}

Main ()
{
int ival=100;
pthread_t th;
...
Pthread_create (&th, NULL, Pfunc, (void *) ival);
}

If you encounter more than one number of parameters. Just wrap it up in struct, pointer it over.

struct test
{
int no;
Char name[80];
};

void Pfunc (void *data)
{
struct Test tt = (struct test*) data
...
}

Main ()
{
struct test itest
pthread_t th;
...
Itest.no=100;
strcpy (Itest.name, "Hello");
...
Pthread_create (&th, NULL, Pfunc, (void *) & itest);
..
}