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GETDIRENTRIES(2)            BSD System Calls Manual           GETDIRENTRIES(2)

NAME
     getdirentries -- get directory entries in a filesystem independent format

SYNOPSIS
     #include <dirent.h>
     #include <sys/types.h>
     #include <sys/dirent.h>

     int
     getdirentries(int fd, char *buf, int nbytes, long *basep);

DESCRIPTION
     Getdirentries() 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 trans-ferred. transferred.
     ferred.  Nbytes must be greater than or equal to the block size associated with the file, see stat(2).
     Some filesystems may not support getdirentries() with buffers smaller than this size.

     The data in the buffer is a series of dirent structures (see dir(5))

     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(2)) have the same d_fileno.  Users of getdirentries() should skip
     entries with d_fileno = 0, as such entries represent files which have been deleted but not yet removed
     from the directory entry.  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.  Thus the actual size of d_name may vary from 1 to MAXNAMELEN + 1.
     d_type is a integer representing the type of the directory entry.  The following types are defined in
     <sys/dirent.h>:

           #define DT_UNKNOWN       0
           #define DT_FIFO          1
           #define DT_CHR           2
           #define DT_DIR           4
           #define DT_BLK           6
           #define DT_REG           8
           #define DT_LNK          10
           #define DT_SOCK         12
           #define DT_WHT          14

     Entries may be separated by extra space.  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.

     Getdirentries() writes the position of the block read into the location pointed to by basep.  Alterna-tively, Alternatively,
     tively, the current position pointer may be set and retrieved by lseek(2).  The current position
     pointer should only be set to a value returned by lseek(2), a value returned in the location pointed to
     by basep, or zero.

NOTES
     getdirentries() should rarely be used directly; instead, opendir(3) and readdir(3) should be used.

     As of Mac OS X 10.6, getdirentries() is deprecated, and it is recommended that applications use
     readdir(3) rather than using getdirentries() directly.  Due to limitations with the system call,
     getdirentries() will not work with 64-bit inodes; in order to use getdirentries(),
     _DARWIN_NO_64_BIT_INODE must be defined.  See stat(2) for more information on _DARWIN_NO_64_BIT_INODE
     and its other effects.

RETURN VALUES
     If successful, the number of bytes actually transferred is returned.  Otherwise, -1 is returned and the
     global variable errno is set to indicate the error.

ERRORS
     Getdirentries() will fail if:

     [EBADF]            fd is not a valid file descriptor open for reading.

     [EFAULT]           Either buf or basep point outside the allocated address space.

     [EIO]              An I/O error occurred while reading from or writing to the file system.

SEE ALSO
     lseek(2), open(2), stat(2), opendir(3), readdir(3), dir(5)

HISTORY
     The getdirentries() function first appeared in 4.4BSD.

BSD                              June 9, 1993                              BSD