opensolaris man page for readdir

readdir(3UCB)					     SunOS/BSD Compatibility Library Functions					     readdir(3UCB)

NAME
       readdir - 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 actu-
       ally read.

RETURN VALUES
       The readdir() function returns NULL on failure and sets	errno to indicate 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_NONBLOCK 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       EBADF	    The file descriptor determined by the DIR stream is no longer valid.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 message.

       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 control-
		    ling  terminal,  and  either  the  process	is  ignoring 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 ALSO
       cc(1B), getdents(2), readdir(3C), scandir(3UCB), lf64(5)

NOTES
       Use of these interfaces should be restricted to only applications written on  BSD platforms.  Use of these interfaces with any of the  sys-
       tem libraries or in multi-thread applications is unsupported.

SunOS 5.11							    30 Oct 2007 						     readdir(3UCB)