diff --git a/components/dfs/include/dfs_file.h b/components/dfs/include/dfs_file.h
index 87a178d0264ae2edbb14b145f40bb94f7a623c4e..a574bdc33425f3caa5ee9e008673af6fced602b2 100644
--- a/components/dfs/include/dfs_file.h
+++ b/components/dfs/include/dfs_file.h
@@ -36,6 +36,7 @@ int dfs_file_read(struct dfs_fd *fd, void *buf, rt_size_t len);
 int dfs_file_getdents(struct dfs_fd *fd, struct dirent *dirp, rt_size_t nbytes);
 int dfs_file_unlink(const char *path);
 int dfs_file_write(struct dfs_fd *fd, const void *buf, rt_size_t len);
+int dfs_file_flush(struct dfs_fd *fd);
 int dfs_file_lseek(struct dfs_fd *fd, rt_off_t offset);
 int dfs_file_stat(const char *path, struct stat *buf);
 int dfs_file_rename(const char *oldpath, const char *newpath);