blocks|key|373129|text|gdb可能只是向您展示字符串类内部的字节字符串解释。试着验证/解决以下问题：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|373130|$+print+str.c_str()|code-block|syntax|javascript|373131|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

gdb is probably just showing you the byte-string-interpretation of the string class' internals. Try this to verify/work around:

<pre><code>$ print str.c_str()
</code></pre>

blocks|key|2492319|text|是否使用调试信息编译了二进制文件？就像g%2B%2B+-g+test.cpp|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|2492320|我公司正在显示正确的信息：|2492321|(gdb)+p+s
$2+=+{static+npos+=+<optimized+out>,+
++_M_dataplus+=+{<std::allocator<char>>+=+{<__gnu_cxx::new_allocator<char>>+=+{<No+data+fields>},+<No+data+fields>},+_M_p+=+0x804b014+"Hello+world"}}|code-block|syntax|javascript|2492322|entityMap^0|J|F|0|0|0^^$0|@$1|2|3|4|5|6|7|O|8|@$9|P|A|Q|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|R|8|@]|D|@]|E|$]]|$1|H|3|I|5|J|7|S|8|@]|D|@]|E|$K|L]]|$1|M|3|-4|5|6|7|T|8|@]|D|@]|E|$]]]|N|$]]

Did you compile your binary with debug information? Like <code>g++ -g test.cpp</code>

Mine is showing correct information:

<pre><code>(gdb) p s
$2 = {static npos = &lt;optimized out&gt;, 
 _M_dataplus = {&lt;std::allocator&lt;char&gt;&gt; = {&lt;__gnu_cxx::new_allocator&lt;char&gt;&gt; = {&lt;No data fields&gt;}, &lt;No data fields&gt;}, _M_p = 0x804b014 "Hello world"}}
</code></pre>

blocks|key|373183|text|您有GCC的坏版本，或GDB，或者您试图在错误的地方打印字符串。如下所示(在启用STL漂亮打印机的情况下使用g%2B%2B+(Ubuntu+4.4.3-4ubuntu5)+4.4.3和GNU+gdb+(GDB)+7.2.50.20110127-cvs+)：|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|373184|#include+<string>
#include+<iostream>

void+function+(std::string+str)
{
++std::cout+<<+str+<<+std::endl;
}

int+main()
{
++std::string+str+=+"random";
++function(str);
}

$+g%2B%2B+-g+t.cc+&&+gdb+-q+./a.out
Reading+symbols+from+/usr/local/tmp/a.out...done.
(gdb)+b+function
Breakpoint+1+at+0x400b30:+file+t.cc,+line+6.
(gdb)+run

Breakpoint+1,+function+(str="random")+at+t.cc:6
6+++++std::cout+<<+str+<<+std::endl;
(gdb)+p+str
$1+=+"random"
(gdb)+q|code-block|syntax|javascript|373185|您可能应该将字符串作为const引用传递到函数中。|373186|entityMap^0|1I|X|2G|X|0|0|0^^$0|@$1|2|3|4|5|6|7|O|8|@$9|P|A|Q|B|C]|$9|R|A|S|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|T|8|@]|D|@]|E|$I|J]]|$1|K|3|L|5|6|7|U|8|@]|D|@]|E|$]]|$1|M|3|-4|5|6|7|V|8|@]|D|@]|E|$]]]|N|$]]

You have a broken version of GCC, or GDB, or you are trying to print the string at the wrong place. Here is what it should look like (using <code>g++ (Ubuntu 4.4.3-4ubuntu5) 4.4.3</code> and <code>GNU gdb (GDB) 7.2.50.20110127-cvs</code> with STL pretty printers enabled):

<pre><code>#include &lt;string&gt;
#include &lt;iostream&gt;

void function (std::string str)
{
 std::cout &lt;&lt; str &lt;&lt; std::endl;
}

int main()
{
 std::string str = "random";
 function(str);
}

$ g++ -g t.cc &amp;&amp; gdb -q ./a.out
Reading symbols from /usr/local/tmp/a.out...done.
(gdb) b function
Breakpoint 1 at 0x400b30: file t.cc, line 6.
(gdb) run

Breakpoint 1, function (str="random") at t.cc:6
6 std::cout &lt;&lt; str &lt;&lt; std::endl;
(gdb) p str
$1 = "random"
(gdb) q
</code></pre>

P.S. You should probably pass the string into function as a const reference.

blocks|key|2492408|text|由于任何原因，GDB可能缺少STL的调试信息。使用Employed+Russian's+example和g%2B%2B+(GCC)+4.3.4+20090804+(版本)1和GNUGDB6.8.0.20080328-cvs(cygwin-专用)，我得到以下输出：|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|2492409|(gdb)+p+str
$1+=+{static+npos+=+<optimized+out>,
++_M_dataplus+=+{<std::allocator<char>>+=+{<__gnu_cxx::new_allocator<char>>+=+{<
No+data+fields>},+<No+data+fields>},+_M_p+=+0x28cce8+"$▒▒"}}|code-block|syntax|javascript|2492410|这是对std::string中原始数据字段的解释。要获得实际的字符串数据，我必须将_M_p字段重新解释为指针：|style|CODE|2492411|(gdb)+p+*(char**)str._M_dataplus._M_p
$2+=+0xd4a224+"random"|2492412|entityMap|0|LINK|mutability|MUTABLE|url|https://stackoverflow.com/questions/4830279/print-command-in-gdb-return-035-on-strings/4830536#4830536^0|P|Q|0|0|0|3|B|15|4|0|0^^$0|@$1|2|3|4|5|6|7|W|8|@]|9|@$A|X|B|Y|1|Z]]|C|$]]|$1|D|3|E|5|F|7|10|8|@]|9|@]|C|$G|H]]|$1|I|3|J|5|6|7|11|8|@$A|12|B|13|K|L]|$A|14|B|15|K|L]]|9|@]|C|$]]|$1|M|3|N|5|F|7|16|8|@]|9|@]|C|$G|H]]|$1|O|3|-4|5|6|7|17|8|@]|9|@]|C|$]]]|P|$Q|$5|R|S|T|C|$U|V]]]]

GDB is probably missing debug information for the STL for whatever reason. Using <a href="https://stackoverflow.com/questions/4830279/print-command-in-gdb-return-035-on-strings/4830536#4830536">Employed Russian's example</a> with g++ (GCC) 4.3.4 20090804 (release) 1 and GNU gdb 6.8.0.20080328-cvs (cygwin-special), I get the following output:

<pre><code>(gdb) p str
$1 = {static npos = &lt;optimized out&gt;,
 _M_dataplus = {&lt;std::allocator&lt;char&gt;&gt; = {&lt;__gnu_cxx::new_allocator&lt;char&gt;&gt; = {&lt;
No data fields&gt;}, &lt;No data fields&gt;}, _M_p = 0x28cce8 "$▒▒"}}
</code></pre>

Which is an interpretation of the raw data fields in <code>std::string</code>. To get the actual string data, I have to reinterpret the <code>_M_p</code> field as a pointer:

<pre><code>(gdb) p *(char**)str._M_dataplus._M_p
$2 = 0xd4a224 "random"
</code></pre>

blocks|key|373222|text|有同样的问题，解决了包括iostream库。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|373223|entityMap^0|C|8|0^^$0|@$1|2|3|4|5|6|7|H|8|@$9|I|A|J|B|C]]|D|@]|E|$]]|$1|F|3|-4|5|6|7|K|8|@]|D|@]|E|$]]]|G|$]]

Had the same problem, solved including <code>iostream</code> library.

Say I have the code:

<pre><code>std::string str = "random";

function(str);

void function (std::string str)
{
 std::cout &lt;&lt; str &lt;&lt; std::endl;
}
</code></pre>

If I step through this code in gdb and then go into the function and do <code>p str</code> it would print out something like this <code>\362\241</code> but the cout will print to the screen the correct string <code>random</code>. Has anyone seen this before if so what should I do? Am I using the print command wrong in gdb or does it have something to do with how the compiler interprets the string?

Why does the print command in gdb return \035 for C++ std::strings?

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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说我有密码：std::string str = "random";function(str);void function (std::string str){ std::cout << str << std::endl;}如果我在gdb中遍历这段代码，然后进入函数并执行p str，它会打印出类似于这个\362\241...

问为什么gdb中的print命令返回C++ std：：string的\035？
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问为什么gdb中的print命令返回C++ std：：string的\035？EN