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readdir(2)


NAME

   readdir - read directory entry

SYNOPSIS

   int readdir(unsigned int fd, struct old_linux_dirent *dirp,
               unsigned int count);

   Note: There is no glibc wrapper for this system call; see NOTES.

DESCRIPTION

   This is not the function you are interested in.  Look at readdir(3) for
   the POSIX conforming C library interface.  This page documents the bare
   kernel system call interface, which is superseded by getdents(2).

   readdir()  reads  one  old_linux_dirent  structure  from  the directory
   referred to by the file descriptor fd into the  buffer  pointed  to  by
   dirp.   The  argument  count  is  ignored; at most one old_linux_dirent
   structure is read.

   The old_linux_dirent structure is declared as follows:

       struct old_linux_dirent {
           long  d_ino;              /* inode number */
           off_t d_off;              /* offset to this old_linux_dirent */
           unsigned short d_reclen;  /* length of this d_name */
           char  d_name[NAME_MAX+1]; /* filename (null-terminated) */
       }

   d_ino is an inode number.  d_off is the distance from the start of  the
   directory  to  this  old_linux_dirent.  d_reclen is the size of d_name,
   not counting the terminating null  byte  ('\0').   d_name  is  a  null-
   terminated filename.

RETURN VALUE

   On  success,  1  is  returned.  On end of directory, 0 is returned.  On
   error, -1 is returned, and errno is set appropriately.

ERRORS

   EBADF  Invalid file descriptor fd.

   EFAULT Argument points outside the calling process's address space.

   EINVAL Result buffer is too small.

   ENOENT No such directory.

   ENOTDIR
          File descriptor does not refer to a directory.

CONFORMING TO

   This system call is Linux-specific.

NOTES

   Glibc does not provide a wrapper for this system call;  call  it  using
   syscall(2).   You  will  need  to define the old_linux_dirent structure
   yourself.  However, probably you should use readdir(3) instead.

   This system call does not exist on x86-64.

SEE ALSO

   getdents(2), readdir(3)

COLOPHON

   This page is part of release 4.09 of the Linux  man-pages  project.   A
   description  of  the project, information about reporting bugs, and the
   latest    version    of    this    page,    can     be     found     at
   https://www.kernel.org/doc/man-pages/.



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