您正在使用相当旧的内核，因此我不得不进行一些挖掘.处理此类问题的一种较简单的方法是查看信息是否位于/proc中，并查看其作用.如果我们在fs/proc中用grep替换cwd，我们会发现:

Your working on quite an old kernel so I've had to do some digging. One of the easier ways to deal with this sort of thing is see if the information is in /proc and look at what it does. If we grep for cwd in fs/proc we find:

static int proc_cwd_link(struct inode *inode, struct dentry   **dentry,   struct vfsmount **mnt)
{
    struct fs_struct *fs;
    int result = -ENOENT;
    task_lock(inode->u.proc_i.task);
    fs = inode->u.proc_i.task->fs;
    if(fs)
        atomic_inc(&fs->count);
    task_unlock(inode->u.proc_i.task);
    if (fs) {
        read_lock(&fs->lock);
        *mnt = mntget(fs->pwdmnt);
        *dentry = dget(fs->pwd);
        read_unlock(&fs->lock);
        result = 0;
        put_fs_struct(fs);
    }
    return result;
}

proc的inode指向任务(inode-> u.proc_i.task，也由task_lock()东西提供).查看task_struct定义，它有对struct fs_struct * fs的引用，该文件具有pwd的dentry指针.但是，将dentry条目转换为实际名称是另一项工作.

The proc inode points to the task (inode->u.proc_i.task, also given away by the task_lock() stuff). Looking at the task_struct definition it has a reference to struct fs_struct *fs which has the dentry pointers for the pwd. Translating the dentry entry to an actual name is another exercise however.