|
"globalvar");
if (ret)
{
printk("globalvar unregister failure");
}
else
{
printk("globalvar unregister success");
}
}
static ssize_t globalvar_read(struct file *filp, char *buf, size_t len, loff_t *off)
{
//获得信号量
if (down_interruptible(&sem))
{
return - ERESTARTSYS;
}
//将global_var从内核空间复制到用户空间
if (copy_to_user(buf, &global_var, s 页码：[1] [2] [3] [4] [5] [6] 第4页、共6页 |
