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    <p>First ensure that your <code>do while</code> block works as expected.</p> <p>Concerning you question</p> <p>As we know one dimensional array can be think as pointer to memory block. so </p> <pre><code>char *ar = recvbuf ; char x1= *ar; //will get first byte (index 0) char x2=*(ar+1); //will get second byte (index 1) </code></pre> <p>Also as array and pointer in our case can be used interchangeable We can access as indexed way too</p> <pre><code> char x1=ar[0];// the same as *ar char x2=ar[1]; //= *(ar+1); </code></pre> <p>As you see char will move one byte, but in our case we want to move 4 bytes. so we will make our pointer to point to int.</p> <pre><code> int *intarr=(int *) recvbuf ; //recvbuf is address </code></pre> <p>now we can access and fetch ints using the same syntax</p> <pre><code> int x1=*intarr; int x2= *(intarr+1); // *((int*)(ar+4)) //or int x1=intarr[0]; </code></pre> <p>And note that if <code>inarr</code> point to for example to address <code>00004</code> , <code>(inarr+1)</code> will point to <code>00004+ 4=00008th</code> address. Cause pointer arithmetic will know that next int address will be obtained using <code>addr+sizeof(int)</code>.</p> <p>Next issue. Bytes order can be different. see <a href="http://en.wikipedia.org/wiki/Bigendian" rel="nofollow noreferrer">endianness</a> On that case we have to make conversion. either we will write our functions. or we can use <code>htonl ntohl</code> . Or see this manual conversion <a href="https://stackoverflow.com/questions/2182002/convert-big-endian-to-little-endian-in-c-without-using-provided-func">endiannes conversion on stackoverflow</a></p> <p>Then coming to my code: <code>uint32_t *endp=(uint32_t*)(recvbuf+iResult);</code> will point to end of our array. so we will increment our pointer until it be equal to endp; <code>while(p&lt;endp) ++p;</code> and simple we will use <code>*</code> dereference operator to get that value. after <code>++p p</code> will point to next int block,and fetching <code>uint32_t</code> from that address will be equal to <code>*p</code>. And we will increment that until <code>endp</code></p> <p>Another option just to use index syntax. so we have to first calculate length of our array. How many ints we got in our array .this will be equal <code>iResult/sizeof(uint32_t)</code> <code>iResult our length in bytes</code>. After that we can access index using <code>*(p+index)</code> or more nice way <code>p[index]</code></p> <pre><code> ... uint32_t *p=(uint32_t*)recvbuf; uint32_t *endp=(uint32_t*)(recvbuf+iResult); //here is accessing while(p&lt;endp){ //ntohl(*p) if it was send from begin endian uint32_t value=*p;p++; } //or uint32_t *p=(uint32_t*)recvbuf; size_t len=iResult/sizeof(uint32_t); // for(int i=0;i&lt;len;i++){ uint32_t value= p[i]; //and again if there is endian problem solve it using ntonl htonl } </code></pre>
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    1. POConverting bytes to uint32 in C
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    1. COHi. Can you please explain the code in words ?.
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    2. CO@user2292615 see if it is helpful
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