readdir(3UCB) SunOS/BSD Compatibility Library Functions readdir(3UCB)NAMEreaddir - read a directory entry
SYNOPSIS
/usr/ucb/cc [ flag ... ] file ...
#include <sys/types.h>
#include <sys/dir.h>
struct direct *readdir(dirp)
DIR *dirp;
DESCRIPTION
The readdir() function returns a pointer to a structure representing
the directory entry at the current position in the directory stream to
which dirp refers, and positions the directory stream at the next
entry, except on read-only file systems. It returns a NULL pointer
upon reaching the end of the directory stream, or upon detecting an
invalid location in the directory. The readdir() function shall not
return directory entries containing empty names. It is unspecified
whether entries are returned for dot (.) or dot-dot (..). The pointer
returned by readdir() points to data that may be overwritten by another
call to readdir() on the same directory stream. This data shall not be
overwritten by another call to readdir() on a different directory
stream. The readdir() function may buffer several directory entries per
actual read operation. The readdir() function marks for update the
st_atime field of the directory each time the directory is actually
read.
RETURN VALUES
The readdir() function returns NULL on failure and sets errno to indi‐
cate the error.
ERRORS
The readdir() function will fail if one or more of the following are
true:
EAGAIN Mandatory file/record locking was set, O_NDELAY or O_NON‐
BLOCK was set, and there was a blocking record lock.
EAGAIN Total amount of system memory available when reading using
raw I/O is temporarily insufficient.
EAGAIN No data is waiting to be read on a file associated with a
tty device and O_NONBLOCK was set.
EAGAIN No message is waiting to be read on a stream and O_NDELAY
or O_NONBLOCK was set.
EBADF The file descriptor determined by the DIR stream is no
longer valid. This results if the DIR stream has been
closed.
EBADMSG Message waiting to be read on a stream is not a data mes‐
sage.
EDEADLK The read() was going to go to sleep and cause a deadlock
to occur.
EFAULT buf points to an illegal address.
EINTR A signal was caught during the read() or readv() function.
EINVAL Attempted to read from a stream linked to a multiplexor.
EIO A physical I/O error has occurred, or the process is in a
background process group and is attempting to read from
its controlling terminal, and either the process is ignor‐
ing or blocking the SIGTTIN signal or the process group of
the process is orphaned.
ENOENT The current file pointer for the directory is not located
at a valid entry.
ENOLCK The system record lock table was full, so the read() or
readv() could not go to sleep until the blocking record
lock was removed.
ENOLINK fildes is on a remote machine and the link to that machine
is no longer active.
ENXIO The device associated with fildes is a block special or
character special file and the value of the file pointer
is out of range.
EOVERFLOW The value of the direct structure member d_ino cannot be
represented in an ino_t.
USAGE
The readdir() function has a transitional interface for 64-bit file
offsets. See lf64(5).
SEE ALSOcc(1B), getdents(2), readdir(3C), scandir(3UCB), lf64(5)NOTES
Use of these interfaces should be restricted to only applications writ‐
ten on BSD platforms. Use of these interfaces with any of the system
libraries or in multi-thread applications is unsupported.
SunOS 5.10 30 Oct 2007 readdir(3UCB)