DIR(5), dirent(5) 目录文件格式

类型：

文件格式和转换 File formats and conventions

结构体定义：

/* structure describing an open directory. */typedef struct _dirdesc {int     __dd_fd;      /* file descriptor associated with directory */long    __dd_loc;     /* offset in current buffer */long    __dd_size;    /* amount of data returned by getdirentries */char    *__dd_buf;    /* data buffer */int     __dd_len;     /* size of data buffer */long    __dd_seek;    /* magic cookie returned by getdirentries */long    __dd_rewind;  /* magic cookie for rewinding */int     __dd_flags;   /* flags for readdir */pthread_mutex_t __dd_lock; /* for thread locking */struct _telldir *__dd_td; /* telldir position recording */} DIR;

struct dirent {    ino_t      d_ino;    /* file number of entry */    __uint16_t d_reclen; /* length of this record */    __uint8_t  d_type;   /* file type, see below */    __uint8_t  d_namlen;/* length of string in d_name */    char    d_name[255 + 1];/* name must be no longer than this */};

用法：

opendir()函数返回一个指向 DIR 结构的指针
readdir()和closedir()函数以 DIR结构的指针作为函数参数

readdir()函数返回一个指向 dirent 结构的指针