一些实用的纯头文件，无需配置，开箱即用。
在每个文件夹下，包含以下文件：
| 文件 | 介绍 |
|---|---|
| *.h | C头文件，大部分可在C89/C++98下使用，部分功能依赖于平台支持（这些将通过宏进行自动判断） |
| *.hpp | C++头文件，提供对C头文件的简单包装，大多数需要C++11或者更高的版本 |
| *.c | C有关例子 |
| *.cpp | C++有关例子 |
| 文件夹 | 介绍 |
|---|---|
| ulatomic | 原子操作 |
| uldate | 日期时间（类似于JS中的Date） |
| uldbuf | 动态缓冲区 |
| uldecode | 文本编码 |
| uldl | 动态链接库 |
| ulendian | 字节序 |
| ulfd | 文件描述符 |
| ullist | 双向链表 |
| ulmtx | 互斥锁 |
| ulrand | 随机数生成器（使用PCG随机数生成器） |
| ulrb | 红黑树（快速但受限的版本） |
| ulsarr | 只读共享数组（加速切片、拼接等操作） |
| ulstdint | <stdint.h>的兼容头文件（用于部分老编译器） |
| ulutf | UTF相关操作 |
The MIT License (MIT)
Copyright (C) 2023-2024 Jin Cai
Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
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