tst_require_root()

tst_res(TPASS, "getenv(" ENV1 ") = '"ENV_VAL "'");

tst_res(TFAIL, "getenv(" ENV1 ") = '%s', expected '"ENV_VAL "'", ret);

SAFE_MKDIR(MNTPOINT, 0777);

SAFE_MKFS(tst_device->dev, tst_device->fs_type, NULL, NULL);

fd1 = SAFE_OPEN(cleanup, FILE1, O_CREAT | O_RDWR, 0666);

SAFE_CLOSE(fd1);

/*

 *   Copyright (c) International Business Machines  Corp., 2001

 *    07/2001 Ported by Wayne Boyer

 *    06/2017 Modified by Guangwen Feng <fenggw-fnst@cn.fujitsu.com>

 *

 *   This program is free software;  you can redistribute it and/or modify

*   it under the terms of the GNU General Public License as published by

 *   the Free Software Foundation; either version 2 of the License, or

 *   (at your option) any later version.

 *

 *   This program is distributed in the hope that it will be useful,

 *   but WITHOUT ANY WARRANTY;  without even the implied warranty of

 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See

 *   the GNU General Public License for more details.

 *

 *   You should have received a copy of the GNU General Public License

 *   along with this program;  if not, write to the Free Software

 *   Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

这段是当你提交代码到开源社区时（ltp），必须声明，遵循GNU General Public License协议（不知道的可以搜一下）。主要规定代码是否可供别人使用，是否可允许修改，是否可商业使用等等。

 */

/*

 * DESCRIPTION

 *      Open a file with oflag = O_CREAT set, does it set the sticky bit off?

 *      Open a dir with O_DIRECTORY, does it set the S_IFDIR bit on?

 *

 * ALGORITHM

 *      1. open a new file with O_CREAT, fstat.st_mode should not have the

 *         01000 bit on. In Linux, the save text bit is *NOT* cleared.

 *      2. open a new dir with O_DIRECTORY, fstat.st_mode should have the

 *         040000 bit on.

 */

用例描述性文字，如果自己提交，记得写清楚哈

#define _GNU_SOURCE             /* for O_DIRECTORY */

#include <sys/types.h>

#include <sys/stat.h>

#include <fcntl.h>

#include <errno.h>

#include "tst_test.h"

包含有文件，其中"tst_test.h"是调用框架接口，必须包含

#define TEST_FILE       "testfile"

#define TEST_DIR        "testdir"

static int fd;

static struct tcase {

        char *filename;

        int flag;

        mode_t mode;

        unsigned short tst_bit;

        char *desc;

} tcases[] = {

        {TEST_FILE, O_RDWR | O_CREAT, 01444, S_ISVTX, "Sticky bit"},

        {TEST_DIR, O_DIRECTORY, 0, S_IFDIR, "Directory bit"}

};

变量和用例初始化，这里提一下，为了代码的可扩展性，系统调用参数尽量提取出来，使用结构体数组存储，方便新增或者删除用例。用例执行部分直接open(tcases[0]->filename,tcases[0]->flag…)。

static void verify_open(unsigned int n)

{

        struct tcase *tc = &tcases[n];

        struct stat buf;

        TEST(open(tc->filename, tc->flag, tc->mode));

        fd = TEST_RETURN;

        if (fd == -1) {

                tst_res(TFAIL, "Cannot open a file");

                return;

        }

        SAFE_FSTAT(fd, &buf);

        if (!(buf.st_mode & tc->tst_bit))

                tst_res(TFAIL, "%s is cleared unexpectedly", tc->desc);

        else

                tst_res(TPASS, "%s is set as expected", tc->desc);

        SAFE_CLOSE(fd);

        if (S_ISREG(buf.st_mode))

    SAFE_UNLINK(tc->filename);

}

verify_open（）用例主体

static void setup(void)

{

        SAFE_MKDIR(TEST_DIR, 0755);

}

setup初始化

static void cleanup(void)

{

        if (fd > 0)

                SAFE_CLOSE(fd);

}

cleanup清理环境

static struct tst_test test = {

        .tcnt = ARRAY_SIZE(tcases),

        .needs_tmpdir = 1,

        .setup = setup,

        .cleanup = cleanup,

        .test = verify_open,

};

架构声明，声明用例数组，函数等，框架会直接调用执行。