GETDIRENTRIES(2-BSD)RISC/os Reference Manual GETDIRENTRIES(2-BSD)



NAME
     getdirentries - gets directory entries in a filesystem
     independent format

SYNOPSIS
     #include <sys/dir.h>

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

DESCRIPTION
     getdirentries attempts to put directory entries from the
     directory referenced by the file descriptor fd into the
     buffer pointed to by buf, in a filesystem independent for-
     mat.  Up to nbytes of data will be transferred.  nbytes must
     be greater than or equal to the block size associated with
     the file (see stat(2)).  Sizes less than this may cause
     errors on certain filesystems.

     The data in the buffer is a series of direct structures each
     containing the following entries:

          unsigned long  d_fileno;
          unsigned short d_reclen;
          unsigned short d_namlen;
          char           d_name[MAXNAMELEN + 1]; /* see below */

     The d_fileno entry is a number which is unique for each dis-
     tinct file in the filesystem.  Files that are linked by hard
     links (see link(2)) have the same d_fileno.  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.  Thus
     the actual size of d_name may vary from 2 to MAXNAMELEN + 1.

     The structures are not necessarily tightly packed.  The
     d_reclen entry may be used as an offset from the beginning
     of a direct structure to the next structure, if any.

     Upon return, 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
     is not necessarily incremented by the number of bytes
     returned by getdirentries.  If the value returned is zero,
     the end of the directory has been reached.  The current
     position pointer may be set and retrieved by lseek(2).  get-
     direntries writes the position of the block read into the
     location pointed to by basep.  It is not safe to set the
     current position pointer to any value other than a value



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GETDIRENTRIES(2-BSD)RISC/os Reference Manual GETDIRENTRIES(2-BSD)



     previously returned by lseek(2) or a value previously
     returned in the location pointed to by basep or zero.

RETURN VALUE
     If successful, the number of bytes actually transferred is
     returned.  Otherwise, a -1 is returned and the global vari-
     able errno is set to indicate the error.

ERRORS
     getdirentries will fail if one or more of the following are
     true:

     EBADF     fd is not a valid file descriptor open for read-
               ing.

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

     EIO       An I/O error occurred while reading from or writ-
               ing to the file system.

     EINTR     A read from a slow device was interrupted before
               any data arrived by the delivery of a signal.

SEE ALSO
     open(2), lseek(2).





























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