blocks|key|1050793|text|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1050794|到目前为止我还没有找到任何解决这个困境的方法|blockquote|1050795|1050796|1050797|您必须使用一次打印一个(可数)事物的函数。您可能希望实现的示例接口如下所示：|1050798|print_string("Hello");
print_int(5);
print_char('\n');|code-block|syntax|javascript|1050799|entityMap^0|0|0|0|0|0|0^^$0|@$1|2|3|-4|4|5|6|O|7|@]|8|@]|9|$]]|$1|A|3|B|4|C|6|P|7|@]|8|@]|9|$]]|$1|D|3|-4|4|5|6|Q|7|@]|8|@]|9|$]]|$1|E|3|-4|4|5|6|R|7|@]|8|@]|9|$]]|$1|F|3|G|4|5|6|S|7|@]|8|@]|9|$]]|$1|H|3|I|4|J|6|T|7|@]|8|@]|9|$K|L]]|$1|M|3|-4|4|5|6|U|7|@]|8|@]|9|$]]]|N|$]]

<blockquote>
so far I am unable to find any solution for this predicament
</blockquote>
You have to use functions that print one (countable) things at a time. An example interface you might want to implement might look like the following:
<pre><code>print_string(&quot;Hello&quot;);
print_int(5);
print_char('\n');
</code></pre>

blocks|key|499504|text|在Linux上，运行在现代x86_64处理器上：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|499505|int+main()
{
++++char+*s+=+"Hello,+World!\n";
++++long+l+=+14;
++++long+fd+=+1;
++++long+syscall+=+1;
++++long+ret+=+0;
++++__asm__("syscall"
++++++++++++:+"=a"(ret)
++++++++++++:+"a"(syscall),
++++++++++++++"D"(fd),
++++++++++++++"S"(s),
++++++++++++++"d"(l));
++++return+0;
}|code-block|syntax|javascript|499506|输出：|499507|Hello,+World!|499508|entityMap^0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|N|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|O|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|P|8|@]|9|@]|A|$E|F]]|$1|K|3|-4|5|6|7|Q|8|@]|9|@]|A|$]]]|L|$]]

On Linux, running on a modern x86_64 processor:
<pre><code>int main()
{
 char *s = &quot;Hello, World!\n&quot;;
 long l = 14;
 long fd = 1;
 long syscall = 1;
 long ret = 0;
 __asm__(&quot;syscall&quot;
 : &quot;=a&quot;(ret)
 : &quot;a&quot;(syscall),
 &quot;D&quot;(fd),
 &quot;S&quot;(s),
 &quot;d&quot;(l));
 return 0;
}
</code></pre>
Output:
<pre><code>Hello, World!
</code></pre>

blocks|key|1050889|text|因此，我开始探索如何编写我自己的printf语句。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1050890|1050891|大多数MISRA系统都是嵌入式系统，其中printf只是UART库的一些臃肿的包装器。通常的解决方案是开发自己的日志/消息传递工具。不一定是基于UART的，也可能是一些其他串行总线，或仅仅8个并行数据或一些LCD/7-seg.所有这些都取决于您需要显示什么，以及您是否打算将其作为生产代码的一部分。|offset|length|style|CODE|1050892|因此，如何做到这一点是高度特定于项目的，它通常更多的是一个系统设计和电子问题，而不是编程问题。|1050893|编辑|1050894|由于您似乎正在创建某种通用库，一种解决方案是提供一个API，将字符串返回给调用方，然后让调用方担心如何显示字符串。这使您的lib+MISRA-C兼容，同时允许调用方以任何特定于应用程序的方式打印字符串。例如：|1050895|void+lib_getmsg+(char*+msg,+size_t+bufsize);|code-block|syntax|javascript|1050896|其中"lib“是库的前缀。将字符串分配留给调用方。或者，老式的方式：|1050897|lib_result_t++lib_dosomething+(void);

//+Returns+LIB_OK+if+went+OK,+returns+LIB_ERR+in+case+of+errors.
//+To+get+more+information,+call+lib_get_lastmsg.

const+char*+lib_get_lastmsg+(void);|1050898|这将返回指向由库分配的内部static字符串的指针。这样做的缺点是，它在多进程环境中不能很好地工作。|1050899|entityMap^0|0|0|K|6|0|0|0|0|0|0|0|D|6|0^^$0|@$1|2|3|4|5|6|7|11|8|@]|9|@]|A|$]]|$1|B|3|-4|5|6|7|12|8|@]|9|@]|A|$]]|$1|C|3|D|5|6|7|13|8|@$E|14|F|15|G|H]]|9|@]|A|$]]|$1|I|3|J|5|6|7|16|8|@]|9|@]|A|$]]|$1|K|3|L|5|6|7|17|8|@]|9|@]|A|$]]|$1|M|3|N|5|6|7|18|8|@]|9|@]|A|$]]|$1|O|3|P|5|Q|7|19|8|@]|9|@]|A|$R|S]]|$1|T|3|U|5|6|7|1A|8|@]|9|@]|A|$]]|$1|V|3|W|5|Q|7|1B|8|@]|9|@]|A|$R|S]]|$1|X|3|Y|5|6|7|1C|8|@$E|1D|F|1E|G|H]]|9|@]|A|$]]|$1|Z|3|-4|5|6|7|1F|8|@]|9|@]|A|$]]]|10|$]]

<blockquote>
so I set out on a quest to find out how I can write my own printf statement
</blockquote>
Most MISRA-C systems are embedded systems where <code>printf</code> is just some bloated wrapper around an UART library. The usual solution is to develop your own logging/messaging tool instead. Not necessarily UART-based, might as well some other serial bus, or just 8 parallel data or some LCD/7-seg... all depending on what you need to display and if you intend for this to be part of the production code or not.
So how to do this is highly project-specific and it's typically more of a system design and electronics problem than a programming one.
EDIT
Since you seem to be making some sort of general-purpose library, one solution is to simply provide an API that returns strings to the caller, then let the caller worry about how to present them. That makes your lib MISRA-C compliant, while allowing the caller to print strings in whatever application-specific way they have available. For example:
<pre><code>void lib_getmsg (char* msg, size_t bufsize);
</code></pre>
Where &quot;lib&quot; is some prefix for your library. Leave string allocation to the caller. Alternatively, the old-fashioned way:
<pre><code>lib_result_t lib_dosomething (void);

// Returns LIB_OK if went OK, returns LIB_ERR in case of errors.
// To get more information, call lib_get_lastmsg.

const char* lib_get_lastmsg (void);
</code></pre>
This returns a pointer to an internal <code>static</code> string allocated by your library. The downside of this is that it won't work well in multi-process environments.

blocks|key|1896372|text|您需要了解MISRA准则的基本原理，了解在其中使用的上下文，以及您自己的代码的情况。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1896373|你也需要明白，米斯拉的指导原则是不应该盲目遵循的一种刻板思维.然后，您需要了解，在米斯拉的那些好人提供了几章有用的材料之前，实际的指导方针。其中一部分是偏离程序。|1896374|如果你能证明为什么你觉得你需要违反一条准则，那么就使用指定的偏差过程。这要求您了解违规行为的性质，以及如何确保应用程序的完整性。|1896375|如果你真的需要使用printf()并且你可以证明这是正确的，那么就用一个偏差来使用它。|offset|length|style|CODE|1896376|entityMap^0|0|0|0|9|8|0^^$0|@$1|2|3|4|5|6|7|N|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|O|8|@]|9|@]|A|$]]|$1|D|3|E|5|6|7|P|8|@]|9|@]|A|$]]|$1|F|3|G|5|6|7|Q|8|@$H|R|I|S|J|K]]|9|@]|A|$]]|$1|L|3|-4|5|6|7|T|8|@]|9|@]|A|$]]]|M|$]]

You need to understand the rationale for the MISRA C guidelines, understand the context they are used in, and the circumstances of your own code.
You also need to understand that the MISRA Guidelines are not to be blindly followed with a tick-box mentality... you then need to appreciate that those nice folk at MISRA provide several chapters of useful material before the actual guidelines. Part of that is the Deviation procedure.
If you can justify why you feel you need to violate a guidelines, then use the deviation procedure that is specified. This requires you understand the nature of the violation, and what you are going to do to ensure the integrity of your application.
If you genuinely need to use <code>printf()</code> and you can justify that, use it with a deviation

I am new to coding using MISRA C guidelines.
The following are two rules in MISRA C 2004:
Rule 16.1 (required): Functions shall not be defined with a variable number of arguments.
Rule 20.9 (required): The input/output library <code>&lt;stdio.h&gt;</code> shall not be used in production code.
This clearly means that I can't use <code>printf</code> in production code for it to be MISRA C compliant, because <code>printf</code> is a part of <code>&lt;stdio.h&gt;</code> and allows a variable number of arguments. So I set out on a quest to find out how I can write my own <code>printf</code> statement. So far I am unable to find any solution for this predicament. Any help from fellow developers would be appreciated.

Alternatives to printf() for MISRA C : 2004 compliant code

翻译质量差，导致语言生硬或混乱。

没有提供实际的解决方法或示例。

解答不清晰，无法理解或解决问题。

页面排版不美观，阅读体验差。

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我是新的编码使用MISRA C指南。以下是2004年MISRA C.的两项规则：规则16.1 (必需)：函数不能用可变数量的参数定义。规则20.9 (要求)：输入/输出库不得用于生产代码.这显然意味着我不能在生产代码中使用printf使其符合MISRA，因为printf是<stdio.h>的一部分，允许变量数量的参数。...

问MISRA C: 2004兼容代码printf()的替代方案
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问MISRA C: 2004兼容代码printf()的替代方案EN