diff --git a/misc/prototypes.h b/misc/prototypes.h
index c5e7484c8..f017e98a4 100644
--- a/misc/prototypes.h
+++ b/misc/prototypes.h
@@ -501,6 +501,7 @@ int lstat(const char *pathname, void *statbuf);
 
 int chmod(const char *pathname, oct_mode_t mode);
 int fchmod(int fd, oct_mode_t mode);
+int fchmodat(int dirfd, const char *pathname, oct_mode_t mode, int flags);
 void umask(oct_mode_t mask);
 
 int creat(const char *file, oct_mode_t mode);
diff --git a/utils/auto-args.h b/utils/auto-args.h
index d7eecf645..c25c37ba6 100644
--- a/utils/auto-args.h
+++ b/utils/auto-args.h
@@ -232,6 +232,7 @@ static char *auto_args_list =
 	"lstat@arg1/s,arg2/p;"
 	"chmod@arg1/s,arg2/o;"
 	"fchmod@arg1/d32,arg2/o;"
+	"fchmodat@arg1/d32,arg2/s,arg3/o,arg4/d32;"
 	"umask@arg1/o;"
 	"creat@arg1/s,arg2/o;"
 	"creat64@arg1/s,arg2/o;"
@@ -451,6 +452,7 @@ static char *auto_retvals_list =
 	"lstat@retval/d32;"
 	"chmod@retval/d32;"
 	"fchmod@retval/d32;"
+	"fchmodat@retval/d32;"
 	"creat@retval/d32;"
 	"creat64@retval/d32;"
 	"isatty@retval/d32;"