projects / unix-history / blame
| Commit | Line | Data |
|---|---|---|
| ad30fb67 | 1 | /* dir.h 4.3 82/04/19 */ |
| e4a96d2a | 2 | |
| ad30fb67 KM |
3 | /* @(#)ndir.h 4.4 3/30/82 */ |
| 4 | ||
| 5 | /* | |
| 6 | * This sets the "page size" for directories. | |
| 7 | * Requirements are DEV_BSIZE <= DIRBLKSIZ <= MINBSIZE with | |
| 8 | * DIRBLKSIZ a power of two. | |
| 9 | * Dennis Ritchie feels that directory pages should be atomic | |
| 10 | * operations to the disk, so we use DEV_BSIZE. | |
| 11 | */ | |
| 12 | #define DIRBLKSIZ DEV_BSIZE | |
| 13 | ||
| 14 | /* | |
| 15 | * This limits the directory name length. Its main constraint | |
| 16 | * is that it appears twice in the user structure. (u. area) | |
| 17 | */ | |
| 18 | #define MAXNAMLEN 255 | |
| 19 | ||
| 20 | struct direct { | |
| 21 | u_long d_ino; | |
| 22 | short d_reclen; | |
| 23 | short d_namlen; | |
| 24 | char d_name[MAXNAMLEN + 1]; | |
| 25 | /* typically shorter */ | |
| e4a96d2a | 26 | }; |
| ad30fb67 KM |
27 | |
| 28 | struct _dirdesc { | |
| 29 | int dd_fd; | |
| 30 | long dd_loc; | |
| 31 | long dd_size; | |
| 32 | char dd_buf[DIRBLKSIZ]; | |
| 33 | }; | |
| 34 | ||
| 35 | /* | |
| 36 | * useful macros. | |
| 37 | */ | |
| 38 | #undef DIRSIZ | |
| 39 | #define DIRSIZ(dp) \ | |
| 40 | ((sizeof(struct direct) - MAXNAMLEN + (dp)->d_namlen + sizeof(ino_t) - 1) &\ | |
| 41 | ~(sizeof(ino_t) - 1)) | |
| 42 | typedef struct _dirdesc DIR; | |
| 43 | #ifndef NULL | |
| 44 | #define NULL 0 | |
| 45 | #endif | |
| 46 | ||
| 47 | /* | |
| 48 | * functions defined on directories | |
| 49 | */ | |
| 50 | extern DIR *opendir(); | |
| 51 | extern struct direct *readdir(); | |
| 52 | extern long telldir(); | |
| 53 | extern void seekdir(); | |
| 54 | #define rewinddir(dirp) seekdir((dirp), 0) | |
| 55 | extern void closedir(); |