Add sys_fdatasync and sync_data

regression/apps/fdatasync/Makefile

@@ -0,0 +1,5 @@
+# SPDX-License-Identifier: MPL-2.0
+
+include ../test_common.mk
+
+EXTRA_C_FLAGS := -static

regression/apps/fdatasync/fdatasync.c

@@ -0,0 +1,49 @@
+// SPDX-License-Identifier: MPL-2.0
+
+#include <stdio.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <string.h>
+#include <stdlib.h>
+
+void test_fdatasync_on_fs(const char *directory)
+{
+	char filepath[256];
+	snprintf(filepath, sizeof(filepath), "%s/test_fdatasync.txt",
+		 directory);
+
+	int fd =
+		open(filepath, O_WRONLY | O_CREAT | O_TRUNC, S_IRUSR | S_IWUSR);
+	if (fd == -1) {
+		perror("Error opening file");
+		exit(EXIT_FAILURE);
+	}
+
+	char *data = "Hello, fdatasync test!\n";
+	if (write(fd, data, strlen(data)) != strlen(data)) {
+		perror("Error writing data");
+		close(fd);
+		exit(EXIT_FAILURE);
+	}
+
+	if (fdatasync(fd) == -1) {
+		perror("Error syncing data");
+		close(fd);
+		exit(EXIT_FAILURE);
+	}
+
+	printf("Data written and synced on %s\n", directory);
+	close(fd);
+}
+
+int main(int argc, char **argv)
+{
+	if (argc != 2) {
+		printf("Usage: %s <directory>\n", argv[0]);
+		return EXIT_FAILURE;
+	}
+
+	test_fdatasync_on_fs(argv[1]);
+
+	return EXIT_SUCCESS;
+}