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POWhat's a portable way of converting Byte-Order of strings in C
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copied!<p>I am trying to write server that will communicate with any standard client that can make socket connections (e.g. telnet client)</p> <p>It started out as an echo server, which of course did not need to worry about network byte ordering.</p> <p>I am familiar with ntohs, ntohl, htons, htonl functions. These would be great by themselves if I were transfering either 16 or 32-bit ints, or if the characters in the string being sent were multiples of 2 or 4 bytes.</p> <p>I'd like create a function that operates on strings such as:</p> <pre><code>str_ntoh(char* net_str, char* host_str, int len) { uint32_t* netp, hostp; netp = (uint32_t*)&net_str; for(i=0; i < len/4; i++){ hostp[i] = ntoh(netp[i]); } } </code></pre> <p>Or something similar. The above thing assumes that the wordsize is 32-bits. We can't be sure that the wordsize on the sending machine is not 16-bits, or 64-bits right?</p> <p>For client programs, such as telnet, they must be using hton* before they send and ntoh* after they receive data, correct?</p> <p>EDIT: For the people that thing because 1-char is a byte that endian-ness doesn't matter:</p> <pre><code>int main(void) { uint32_t a = 0x01020304; char* c = (char*)&a; printf("%x %x %x %x\n", c[0], c[1], c[2], c[3]); } </code></pre> <p>Run this snippet of code. The output for me is as follows:</p> <pre><code>$ ./a.out 4 3 2 1 </code></pre> <p>Those on powerPC chipsets should get '1 2 3 4' but those of us on intel chipset should see what I got above for the most part.</p>

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