+ char read_out[256];
+
+ // 切换工作目录至 /dev
+ int errno = chdir("/dev");
+ if (errno) {
+ write(STDOUT, "fail to chdir", 15);
+ return;
+ }
+
+ if (getcwd(read_out, sizeof(read_out))) {
+ write(STDOUT, "current working dir: ", 22);
+ write(STDOUT, read_out, 256);
+ write(STDOUT, "\n", 2);
+ }