blocks|key|1011965|text|在Microsoft上，二进制文件应该以二进制模式("rb")打开，而不是以文本模式("r")打开。WAVE文件是二进制文件。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1011966|在这之后，一切都是'-1‘|blockquote|1011967|这个说法是不正确的。你什么都不读了。函数fgetc返回宏常量EOF，它在大多数平台上定义为-1。如果您检查是否为EOF，通过将循环更改为以下内容，这将变得明显起来：|1011968|++++for(int+i=0;i<200;i%2B%2B)
++++{
++++++++int+a+=+fgetc(file);+//the+type+must+be+int,+not+char

++++++++if+(+a+==+EOF+)
++++++++{
++++++++++++printf(+"EOF\n"+);
++++++++++++break;
++++++++}

++++++++printf("%25hhX+",a);
++++}|code-block|syntax|javascript|1011969|当fgetc返回EOF时，这意味着已经到达文件结束或发生了错误。在这种情况下，这是由于文件的结束。|1011970|在Microsoft上，当以文本模式打开文件时，字符代码0x1A将被解释为文件的结尾。根据您发布的屏幕截图，您的文件恰好在文件偏移量0x1A处具有0x28值。这就是为什么只能读取文件偏移量0x27+(十进制中的39)的原因。若要解决此问题，请以二进制模式而不是文本模式打开文件。|1011971|entityMap^0|Q|4|17|3|0|0|K|5|U|3|19|2|1K|3|0|0|1|5|8|3|0|S|4|1U|4|21|4|2M|4|2X|2|0^^$0|@$1|2|3|4|5|6|7|V|8|@$9|W|A|X|B|C]|$9|Y|A|Z|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|10|8|@]|D|@]|E|$]]|$1|I|3|J|5|6|7|11|8|@$9|12|A|13|B|C]|$9|14|A|15|B|C]|$9|16|A|17|B|C]|$9|18|A|19|B|C]]|D|@]|E|$]]|$1|K|3|L|5|M|7|1A|8|@]|D|@]|E|$N|O]]|$1|P|3|Q|5|6|7|1B|8|@$9|1C|A|1D|B|C]|$9|1E|A|1F|B|C]]|D|@]|E|$]]|$1|R|3|S|5|6|7|1G|8|@$9|1H|A|1I|B|C]|$9|1J|A|1K|B|C]|$9|1L|A|1M|B|C]|$9|1N|A|1O|B|C]|$9|1P|A|1Q|B|C]]|D|@]|E|$]]|$1|T|3|-4|5|6|7|1R|8|@]|D|@]|E|$]]]|U|$]]

On Microsoft Windows, binary files should be opened in binary mode (<code>&quot;rb&quot;</code>), not text mode (<code>&quot;r&quot;</code>). A WAVE file is a binary file.
<blockquote>
After this everything reads as '-1'
</blockquote>
This statement is incorrect. You are no longer reading anything. The function <code>fgetc</code> is returning the macro constant <code>EOF</code>, which is defined as <code>-1</code> on most platforms. This should become apparant if you check for <code>EOF</code>, by changing your loop to the following:
<pre><code> for(int i=0;i&lt;200;i++)
 {
 int a = fgetc(file); //the type must be int, not char

 if ( a == EOF )
 {
 printf( &quot;EOF\n&quot; );
 break;
 }

 printf(&quot;%hhX &quot;,a);
 }
</code></pre>
When <code>fgetc</code> returns <code>EOF</code>, this means that either end-of-file has been reached or an error has occurred. In this case, it is due to end-of-file.
On Microsoft Windows, when a file is opened in text mode, the character code <code>0x1A</code> is interpreted as the end of the file. According to your posted screenshot, your file happens to have the value <code>0x1A</code> at file offset <code>0x28</code>. That is the reason why you can only read up to file offset <code>0x27</code> (<code>39</code> in decimal) in the file. To fix this, open the file in binary mode instead of text mode.

blocks|key|1011979|text|“读取文件的正确方法是什么？”|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1011980|下面是附加说明的例子：|1011981|//+#include+<windows.h>+//+Not+needed+for+this+program
#include+<stdio.h>

int+main()+{
++++char+*fname+=+"Eva.wav";+//+re-usable+string

++++FILE+*file+=+fopen(+fname,+"rb"+);+//+NB:+"binary+mode"+for+Windows
++++if(+file+==+NULL+)+{
++++++++fprintf(+stderr,+"Cannot+open+'%25s'\n",+fname+);+//+See?
++++++++exit(+EXIT_FAILURE+);+//+do+not+continue
++++}
++++
++++unsigned+char+buf[+200+];+//+OP+wants+to+'sniff'+first+200+bytes

++++//+"correct"+way+to+read+bytes
++++//+Could+use+loop,+reading+1,+20,+or+50+bytes+at+a+time.+Why?
++++size_t+nRead+=+fread(+buf,+sizeof+buf[0],+sizeof+buf,+file+);

++++fclose(+file+);+//+close+when+no+longer+needed

++++//+only+bytes+loaded,+not+quantity+expected
++++for(+size_t+i+=+0;+i+<+nRead;+i%2B%2B+)
++++++++printf(+"%2502X+",+buf+[+i+]+);+//+"old+school".+may+be+antiquated

++++return+0;
}|code-block|syntax|javascript|1011982|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|K|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|L|8|@]|9|@]|A|$]]|$1|D|3|E|5|F|7|M|8|@]|9|@]|A|$G|H]]|$1|I|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|J|$]]

&quot;What is the right way to read file?&quot;
Annotated example below:
<pre><code>// #include &lt;windows.h&gt; // Not needed for this program
#include &lt;stdio.h&gt;

int main() {
 char *fname = &quot;Eva.wav&quot;; // re-usable string

 FILE *file = fopen( fname, &quot;rb&quot; ); // NB: &quot;binary mode&quot; for Windows
 if( file == NULL ) {
 fprintf( stderr, &quot;Cannot open '%s'\n&quot;, fname ); // See?
 exit( EXIT_FAILURE ); // do not continue
 }
 
 unsigned char buf[ 200 ]; // OP wants to 'sniff' first 200 bytes

 // &quot;correct&quot; way to read bytes
 // Could use loop, reading 1, 20, or 50 bytes at a time. Why?
 size_t nRead = fread( buf, sizeof buf[0], sizeof buf, file );

 fclose( file ); // close when no longer needed

 // only bytes loaded, not quantity expected
 for( size_t i = 0; i &lt; nRead; i++ )
 printf( &quot;%02X &quot;, buf [ i ] ); // &quot;old school&quot;. may be antiquated

 return 0;
}
</code></pre>

This programm reads only 39 bytes. After this everything reads as '-1'
<pre><code>#include &lt;windows.h&gt;
#include &lt;stdio.h&gt;
int main()
{
 FILE *file =fopen(&quot;Eva.wav&quot;,&quot;r&quot;);
 if (file==NULL)
 printf(&quot;heresy read!&quot;);
 
 for(int i=0;i&lt;200;i++)
 {
 char a = fgetc(file);
 printf(&quot;%hhX &quot;,a);
 }
 fclose(file);
 return 0;
}
</code></pre>
<a href="https://i.stack.imgur.com/MeOx4.png" rel="nofollow noreferrer">enter image description here</a>
I rewrite code using fread function. After 39 byte comes something absolute other byte code. Looks like segmented file. But if it so, why fread and fgets result are different?
<pre><code>C:\Users\phoenix\Documents\gccex\serial&gt;a.exe
52 49 46 46 46 FF8C FFA3 0 57 41 56 45 66 6D 74 20 10 0 0 0 1 0 1 0 44 FFAC 0 0 44 FFAC 0 0 1 0 8 0 4C 49 53 54 FF86 FFAA 6A FFFB FFFE 7F 0 0 FF88 2C 40 0 0 0 0 0 0 0 0 0 0 0 0 0 10 15 40 0 0 0 0 0 8 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 11 0 1 10 0 0 0 0 60 7 FF96 0 0 0 0 0 FF86 FFAA 6A FFFB FFFE 7F 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 FFB0 16 40 0 0 0 0 0 10 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 50 13 FF96 0 0 0 0 0 FF83 16 40 0 0 0 0 0 1 0 0 0 0 0 0 0 6 0 0 0 0 0 0 0 70 13 FF96 0 0 0 0 0 FFB0 16 40 0 0 0 0 0 FFFF FFFF FFFF FFFF FFFF FFFF FFFF FFFF FF99 17 40 0 0 0 0 0 10 0 0 0 0 0 0 0 FF99 16 40 0 0 0 0 0 0 0 0 0 0 0 0 0 6 0 0 0 0 0 0
</code></pre>
What is the right way to read file?

fgetc read only 39 bytes from file

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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这个程序只读取39个字节。在这之后，一切都是'-1‘#include <windows.h>#include <stdio.h>int main(){ FILE *file =fopen("Eva.wav","r"); if (file==NULL) printf("heresy read!"...

问fgetc只从文件中读取39个字节。
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问fgetc只从文件中读取39个字节。
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