getdents.2: Fix text relating to DT_UNKNOWN and 'd_type' support

Some file systems provide partial support for 'dt_type',
returning DT_UNKNOWN for cases they don't support.
Update the discussion of 'd_type' and DT_UNKNOWN to
support this.

Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>

diff --git a/man2/getdents.2 b/man2/getdents.2
index 90a3d37bb34ed839b208761d7d59f1a307946196..ca434e0f9ab77ac6e04af82cf670d032b8872272 100644 (file)
--- a/man2/getdents.2
+++ b/man2/getdents.2
@@ -24,7 +24,7 @@
 .\" Modified 22 July 1995 by Michael Chastain <mec@duracef.shout.net>:
 .\"   Derived from 'readdir.2'.
 .\" Modified Tue Oct 22 08:11:14 EDT 1996 by Eric S. Raymond <esr@thyrsus.com>
-.TH GETDENTS 2  2009-10-02 "Linux" "Linux Programmer's Manual"
+.TH GETDENTS 2  2008-10-28 "Linux" "Linux Programmer's Manual"
 .SH NAME
 getdents \- get directory entries
 .SH SYNOPSIS
@@ -115,12 +115,13 @@ This is a Unix domain socket.
 .B DT_UNKNOWN
 The file type is unknown.
 .PP
-Curently,
+Currently,
 .\" kernel 2.6.27
-only ext2, ext3, and ext4 support returning the file type in
+.\" The same sentence is in readdir.2
+only some file systems (among them: ext2, etx3, and ext4)
+have full support returning the file type in
 .IR d_type .
-On other file systems,
-this field is always set to
+All applications must properly handle a return of
 .BR DT_UNKNOWN .
 .SH "RETURN VALUE"
 On success, the number of bytes read is returned.