ultrix man page for getdirentries

getdirentries(2)						System Calls Manual						  getdirentries(2)

Name
       getdirentries - gets directory entries in a generic directory format

Syntax
       #include <sys/dir.h>

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

Description
       The  system  call  puts	directory  entries from the directory referenced by the file descriptor fd into the buffer pointed to by buf, in a
       generic directory format.  Up to nbytes of data are transferred.  The nbytes of data must be greater than or equal to the block size  asso-
       ciated with the file.  For further information, see Sizes less than nbytes can cause errors on certain file systems.

       The data returned in the buffer is a series of direct structures, each containing the following entries:
       unsigned long   d_ino;
       unsigned short  d_reclen;
       unsigned short  d_namlen;
       char	       d_name[MAXNAMLEN + 1];

       The  d_ino  entry  is a number that is unique for each distinct file in the file system.  Files that are linked by hard links have the same
       d_ino .	For further information, see The d_reclen entry is the length, in bytes, of the directory record.  The	d_namlen  entry  specifies
       the  length  of	the file name.	The d_name entry contains a null-terminated file name.	Thus, the actual size of d_name can vary from 2 to
       MAXNAMLEN + 1.

       The generic directory 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 If the value returned  is	zero,  the
       end of the directory has been reached.  The current position pointer may be set and retrieved by The system call 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  pre-
       viously returned by or a value previously returned in the location pointed to by basep or zero.

Return Values
       If  successful,	the number of bytes actually transferred is returned.  Otherwise, a -1 is returned and the global variable errno is set to
       indicate the error.

Diagnostics
       The system call fails under the following conditions:

       EBADF	      The fd is not a valid file descriptor open for reading.

       ENOTDIR	      The fd is not a directory.

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

       EIO	      While reading from or writing to the file system, an I/O error occurred.

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

       EPERM	      The user does not have read permission in the directory.	The system call is not the suggested interface for reading  direc-
		      tories.  The and routines offer a standard interface. See the reference page for information on these routines.

See Also
       close(2), link(2), lseek(2), open(2), stat(2), directory(3)

																  getdirentries(2)