在C/C++編程時,需要獲取目錄下面的文件列表信息。
1.數據結構
struct dirent
{
long d_ino; /* inode number 索引節點號 */
off_t d_off; /* offset to this dirent 在目錄文件中的偏移 */
unsigned short d_reclen; /* length of this d_name 文件名長 */
unsigned char d_type; /* the type of d_name 文件類型 */
char d_name [NAME_MAX+1]; /* file name (null-terminated) 文件名,最長255字符 */
}
struct __dirstream
{
void *__fd; /* `struct hurd_fd' pointer for descriptor. */
char *__data; /* Directory block. */
int __entry_data; /* Entry number `__data' corresponds to. */
char *__ptr; /* Current pointer into the block. */
int __entry_ptr; /* Entry number `__ptr' corresponds to. */
size_t __allocation; /* Space allocated for the block. */
size_t __size; /* Total valid data in the block. */
__libc_lock_define (, __lock) /* Mutex lock for this structure. */
};
typedef struct __dirstream DIR;
{
void *__fd; /* `struct hurd_fd' pointer for descriptor. */
char *__data; /* Directory block. */
int __entry_data; /* Entry number `__data' corresponds to. */
char *__ptr; /* Current pointer into the block. */
int __entry_ptr; /* Entry number `__ptr' corresponds to. */
size_t __allocation; /* Space allocated for the block. */
size_t __size; /* Total valid data in the block. */
__libc_lock_define (, __lock) /* Mutex lock for this structure. */
};
typedef struct __dirstream DIR;
2.程序示例
其中程序中win不支持文件類型(d_type),可以根據文件名稱后綴來判斷文件類型;linux可以直接使用d_type判斷是目錄還是文件。
#include <sys/types.h> #include <dirent.h> #include <unistd.h> #include <stdio.h> int main(){ DIR *dir; struct dirent *ptr; dir = opendir("."); ///open the dir while((ptr = readdir(dir)) != NULL) ///read the list of this dir { #ifdef _WIN32 printf("d_name: %s\n", ptr->d_name); #endif #ifdef __linux printf("d_type:%d d_name: %s\n", ptr->d_type,ptr->d_name); #endif } closedir(dir); return 0; }
程序輸出: