NAME

     VOP_READDIR — read contents of a directory

SYNOPSIS

     #include <sys/param.h>
     #include <sys/dirent.h>
     #include <sys/vnode.h>

     int
     VOP_READDIR(struct vnode *vp, struct uio *uio, struct ucred *cred, int *eofflag,
         int *ncookies, u_long **cookies);

DESCRIPTION

     Read directory entries.

     vp        The vnode of the directory.

     uio       Where to read the directory contents.

     cred      The caller's credentials.

     eofflag   Return end of file status (NULL if not wanted).

     ncookies  Number of directory cookies generated for NFS (NULL if not wanted).

     cookies   Directory seek cookies generated for NFS (NULL if not wanted).
     The directory contents are read into struct dirent structures.  If the on-disc data
     structures differ from this then they should be translated.

LOCKS

     The directory should be locked on entry and will still be locked on exit.

RETURN VALUES

     Zero is returned on success, otherwise an error code is returned.

     If this is called from the NFS server, the extra arguments eofflag, ncookies and cookies are
     given.  The value of *eofflag should be set to TRUE if the end of the directory is reached
     while reading.  The directory seek cookies are returned to the NFS client and may be used
     later to restart a directory read part way through the directory.  There should be one
     cookie returned per directory entry.  The value of the cookie should be the offset within
     the directory where the on-disc version of the appropriate directory entry starts.  Memory
     for the cookies should be allocated using:

             ...;
             *ncookies = number of entries read;
             *cookies = malloc(*ncookies * sizeof(u_long), M_TEMP, M_WAITOK);

ERRORS

     [EINVAL]           An attempt was made to read from an illegal offset in the directory.

     [EIO]              A read error occurred while reading the directory.

SEE ALSO

     vnode(9)

AUTHORS

     This manual page was written by Doug Rabson.