getdirentries(2)getdirentries(2)NAMEgetdirentries - Get directory entries in a file-system independent for‐
mat.
SYNOPSIS
#include <dirent.h>
int getdirentries(
int fd,
char *buf,
int nbytes,
long *basep );
PARAMETERS
Specifies the file descriptor of a directory to be read. Points to a
buffer containing the directory entries as dirent structures. Speci‐
fies the maximum amount of data to be transferred, in bytes. Points to
the position of the block read.
DESCRIPTION
The getdirentries() function reads directory entries from a directory
into a buffer. The entries are returned as dirent structures, a file-
system independent format.
Caution
This call is not the POSIX-defined way to process directory entries.
For POSIX interfaces, use the opendir(), readdir(), and closedir()
library routines for reading and interpreting directory entries.
The nbytes parameter should be greater than or equal to the block size
associated with the file. (See stat(2).) Some file systems do not sup‐
port the getdirentries() function with buffers smaller than this size.
The entries returned by the getdirentries() function into the location
pointed to by buf can be separated by extra space.
The getdirentries() function writes the position of the block read into
the location pointed to by the basep parameter. Alternatively, the cur‐
rent position pointer can be set and retrieved by lseek(). The current
position pointer should only be set to a value returned by lseek(), a
value returned in the location pointed to by basep, or 0 (zero).
Upon successful completion, the actual number of bytes transferred is
returned and the current position pointer associated with the fd param‐
eter is set to point to the next block of entries. The file descriptor
pointer might not advance by the same number of bytes returned by the
getdirentries() function. A value of 0 (zero) is returned when the end
of the directory has been reached.
RETURN VALUES
Upon successful completion, the actual number of bytes transferred is
returned. Otherwise, -1 is returned and errno is set to indicate the
error.
ERRORS
If the getdirentries() function fails, errno is set to one of the fol‐
lowing values: The fd parameter is not a valid file descriptor open for
reading. Either the buf or basep parameter points outside the allo‐
cated address space. Either the fd parameter is not a valid file
descriptor for a directory or the buffer is too small. An I/O error
occurred while the operating system was reading from or writing to the
file system.
SEE ALSO
Functions: lseek(2), open(2), stat(2), closedir(3), opendir(3), read‐
dir(3)getdirentries(2)
