man2/getdents.2

   1 .\" Copyright (C) 1995 Andries Brouwer (aeb@cwi.nl)
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  23 .\" Written 11 June 1995 by Andries Brouwer <aeb@cwi.nl>
  24 .\" Modified 22 July 1995 by Michael Chastain <mec@duracef.shout.net>:
  25 .\"   Derived from 'readdir.2'.
  26 .\" Modified Tue Oct 22 08:11:14 EDT 1996 by Eric S. Raymond <esr@thyrsus.com>
  27 .TH GETDENTS 2  1995-07-22 "Linux 1.3.6" "Linux Programmer's Manual"
  28 .SH NAME
  29 getdents \- get directory entries
  30 .SH SYNOPSIS
  31 .nf
  32 .B #include <unistd.h>
  33 .B #include <linux/types.h>
  34 .B #include <linux/dirent.h>
  35 .B #include <linux/unistd.h>
  36 .B #include <errno.h>
  37 .sp
  38 .B _syscall3(int, getdents, uint, fd, struct dirent *, dirp, uint, count)
  39 .sp
  40 .BI "int getdents(unsigned int " fd ", struct dirent *" dirp ", unsigned int " count );
  41 .fi
  42 .SH DESCRIPTION
  43 This is not the function you are interested in.
  44 Look at
  45 .BR readdir (3)
  46 for the POSIX conforming C library interface.
  47 This page documents the bare kernel system call interface.
  48 .PP
  49 The system call
  50 .B getdents
  51 reads several
  52 .I dirent
  53 structures from the directory
  54 pointed at by
  55 .I fd
  56 into the memory area pointed to by
  57 .IR dirp .
  58 The parameter
  59 .I count
  60 is the size of the memory area.
  61 .PP
  62 The
  63 .I dirent
  64 structure is declared as follows:
  65 .PP
  66 .RS
  67 .nf
  68 struct dirent
  69 {
  70     long d_ino;                 /* inode number */
  71     off_t d_off;                /* offset to next \fIdirent\fP */
  72     unsigned short d_reclen;    /* length of this \fIdirent\fP */
  73     char d_name [NAME_MAX+1];   /* file name (null-terminated) */
  74 }
  75 .fi
  76 .RE
  77 .PP
  78 .I d_ino
  79 is an inode number.
  80 .I d_off
  81 is the distance from the start of the directory to the start of the next
  82 .IR dirent .
  83 .I d_reclen
  84 is the size of this entire
  85 .IR dirent .
  86 .I d_name
  87 is a null-terminated file name.
  88 .PP
  89 This call supersedes
  90 .BR readdir (2).
  91 .SH "RETURN VALUE"
  92 On success, the number of bytes read is returned.
  93 On end of directory, 0 is returned.
  94 On error, \-1 is returned, and
  95 .I errno
  96 is set appropriately.
  97 .SH ERRORS
  98 .TP
  99 .B EBADF
 100 Invalid file descriptor
 101 .IR fd .
 102 .TP
 103 .B EFAULT
 104 Argument points outside the calling process's address space.
 105 .TP
 106 .B EINVAL
 107 Result buffer is too small.
 108 .TP
 109 .B ENOENT
 110 No such directory.
 111 .TP
 112 .B ENOTDIR
 113 File descriptor does not refer to a directory.
 114 .SH "CONFORMING TO"
 115 SVr4, SVID.  SVr4 documents additional ENOLINK, EIO error conditions.
 116 .SH "SEE ALSO"
 117 .BR readdir (2),
 118 .BR readdir (3)