man/man2/chmod.2: Document fchmodat(AT_EMPTY_PATH)

The documentation and behaviour is indentical to the equivalent flag for
fchownat(2).

Signed-off-by: Aleksa Sarai <cyphar@cyphar.com>
Message-ID: <20250619-fchmod-empty-path-v1-1-feff2c63abe4@cyphar.com>
Signed-off-by: Alejandro Colomar <alx@kernel.org>

diff --git a/man/man2/chmod.2 b/man/man2/chmod.2
index 307589481593ffa7e09637b4b9a818c65d500254..671e256ba5256df8893269cb26576ef83395cacf 100644 (file)
--- a/man/man2/chmod.2
+++ b/man/man2/chmod.2
@@ -190,7 +190,30 @@ is absolute, then
 is ignored.
 .P
 .I flags
-can either be 0, or include the following flag:
+can either be 0, or include the following flags:
+.TP
+.BR AT_EMPTY_PATH " (since Linux 6.6)"
+.\" commit 5daeb41a6fc9d0d81cb2291884b7410e062d8fa1
+If
+.I path
+is an empty string, operate on the file referred to by
+.I dirfd
+(which may have been obtained using the
+.BR open (2)
+.B O_PATH
+flag).
+In this case,
+.I dirfd
+can refer to any type of file, not just a directory.
+If
+.I dirfd
+is
+.BR AT_FDCWD ,
+the call operates on the current working directory.
+This flag is Linux-specific; define
+.B _GNU_SOURCE
+.\" Before glibc 2.16, defining _ATFILE_SOURCE sufficed
+to obtain its definition.
 .TP
 .B AT_SYMLINK_NOFOLLOW
 If