#include <stdarg.h>
#include <dlfcn.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/types.h>
#include <fcntl.h>
typedef int (*fcntl_pfn_t)(int fildes, int cmd, ...);
int fcntl(int fildes, int cmd, ...)
{
	fcntl_pfn_t g_sys_fcntl_func    = (fcntl_pfn_t)dlsym(RTLD_NEXT,"fcntl");
	va_list arg_list;
	va_start( arg_list,cmd );
	int ret = -1;
	switch( cmd )
	{
		case F_DUPFD:
		{
			int param = va_arg(arg_list,int);
			ret = g_sys_fcntl_func( fildes,cmd,param );
			break;
		}
		case F_GETFD:
		{
			ret = g_sys_fcntl_func( fildes,cmd );
			break;
		}
		case F_SETFD:
		{
			int param = va_arg(arg_list,int);
			ret = g_sys_fcntl_func( fildes,cmd,param );
			break;
		}
		case F_GETFL:
		{
			ret = g_sys_fcntl_func( fildes,cmd );
			break;
		}
		case F_SETFL:
		{
			int param = va_arg(arg_list,int);
			int flag = param;
			flag |= O_NONBLOCK;
			ret = g_sys_fcntl_func( fildes,cmd,flag );
			break;
		}
		case F_GETOWN:
		{
			ret = g_sys_fcntl_func( fildes,cmd );
			break;
		}
		case F_SETOWN:
		{
			int param = va_arg(arg_list,int);
			ret = g_sys_fcntl_func( fildes,cmd,param );
			break;
		}
		case F_GETLK:
		{
			struct flock *param = va_arg(arg_list,struct flock *);
			ret = g_sys_fcntl_func( fildes,cmd,param );
			break;
		}
		case F_SETLK:
		{
			struct flock *param = va_arg(arg_list,struct flock *);
			ret = g_sys_fcntl_func( fildes,cmd,param );
			break;
		}
		case F_SETLKW:
		{
			struct flock *param = va_arg(arg_list,struct flock *);
			ret = g_sys_fcntl_func( fildes,cmd,param );
			break;
		}
	}
	va_end( arg_list );
	return ret;
}
int main() {
	int old = fcntl(STDIN_FILENO, F_GETFL);
	printf ("old:%d\n", old);
	fcntl(STDIN_FILENO, F_SETFL, old);
	int _new = fcntl(STDIN_FILENO, F_GETFL);
	printf ("new:%d\n", _new);
}