NAME | SYNOPSIS | FEATURES | DESCRIPTION | RETURN VALUES | ERRORS | ATTRIBUTES | SEE ALSO | HISTORY
#include <sys/types.h> #include <dirent.h>int getdirentries(int fd, char *buf, int nbytes, long *basep);
MSDOSFS, NFS_CLIENT, UFS
The getdirentries function reads directory entries from the directory referenced by the file descriptor fd into the buffer pointed to by buf, in a filesystem--independent format. Up to nbytes of data will be transferred. The nbytes parameter must be greater than or equal to the block size associated with the file, )(see stat(2POSIX)) . Some filesystems may not support getdirentries with buffers smaller than this size.
The data in the buffer is a series of dirent structures, each containing the following entries:
unsigned longR d_fileno; unsigned short d_reclen; unsigned short d_namlen; char d_name[MAXNAMELEN + 1]; /* see below */ |
The d_fileno entry is a number which is unique for each distinct file in the filesystem. Files that are linked by hard links (see link(2POSIX)) have the same d_fileno. The d_reclen entry is the length, in bytes, of the directory record. The d_name entry contains a null terminated file name. The d_namlen entry specifies the length of the file name excluding the null byte. The size of d_name may vary from 1 to MAXNAMELEN + 1.
Entries may be separated by extra spaces. The d_reclen entry may be used as an offset from the start of a dirent structure to the next structure, if any.
The actual number of bytes transferred is returned. The current position pointer associated with fd is set to point to the next block of entries. The pointer may not advance by the number of bytes returned by getdirentries. A value of zero is returned when the end of the directory has been reached.
The getdirentries function writes the position of the block read into the location pointed to by basep. Alternatively, the current position pointer may be set and retrieved using lseek(2POSIX). The current position pointer should only be set to a value returned by lseek(2POSIX), a value returned in the location pointed to by basep, or zero.
If successful, the number of bytes actually transferred is returned. Otherwise, -1 is returned and the global variable errno is set to indicate one of the following error conditions.
fd is not a valid file descriptor open for reading.
In user mode, either buf or basep points outside the allocated address space. In supervisor mode, this is not detected and the target's state is unknown.
An I/O error occurred while reading from or writing to the file system.
See attributes(5) for descriptions of the following attributes:
ATTRIBUTE TYPE | ATTRIBUTE VALUE |
---|---|
Interface Stability | Evolving |
The getdirentries function first appeared in 4.4 BSD.
NAME | SYNOPSIS | FEATURES | DESCRIPTION | RETURN VALUES | ERRORS | ATTRIBUTES | SEE ALSO | HISTORY