htonl

最近的工作是进行程序由 SUN SPARC 向 Intel X86 移植的工作，多数问题都出现在网络字节序的部分，所以拿出来在这部分工作中使用频率较高的几个接口区分比较下：） ntohs =net to host short int 16位 htons=host to net short int 16位 ntohl =net to host long int 32位 htonl=host to net long int 32位 ntohs 简述： 将一个无符号短整形数从网络字节顺序转换为主机字节顺序。 #include u_short PASCAL FAR ntohs( u_short netshort); netshort：一个以网络字节顺序表达的16位数。 注释： 本函数将一个16位数由网络字节顺序转换为主机字节顺序。 返回值：ntohs()返回一个以主机字节顺序表达的数。 htons 简述： 将主机的无符号短整形数转换成网络字节顺序。 #include u_short PASCAL FAR htons( u_short hostshort); hostshort：主机字节顺序表达的16位数。 注释： 本函数将一个16位数从主机字节顺序转换成网络字节顺序。 返回值： htons()返回一个网络字节顺序的值。 ===================================

I've a variable __be32 x; I've a function __u32 foo(void){ __u32 a; return a; } I need to store the return of foo in variable x . x=htonl(foo()); Is it correct? I've a confusion that what are the return types of ntohl() and htonl() . Are they opposite of each other? To check the output, I need to recompile the kernel and I don't want to trouble my system with any errors. So I'm asking here. You can use the macros defined in kernel.h: http://www.bruceblinn.com/linuxinfo/ByteOrder.html The following macros return the value after it has been converted. Note: the linux/kernel.h header file is the

cout << "Hello World !" << endl; For my very first post on stack overflow : When are we supposed to use the htonl function? I have gone through the man page. However, I don't really understand when and how to use it. H ost TO N etwork translation. It makes sure the endian of a 32 bit data value is correct (Big endian) for network transport. ntohl -- N etwork TO H ost -- is used by the receiver to ensure that the endian is correct for the receiver's CPU. Keep an eye out for htons and ntohs for handling 16 bits, and out there somewhere are likely htonll and ntohll for 64 bits. Using all of them

As far as I know, the C library provides no help in serializing numeric values into a non-text byte stream. Correct me if I'm wrong. The most standard tool in use is htonl et al from POSIX. These functions have shortcomings: There is no 64-bit support. There is no floating-point support. There are no versions for signed types. When deserializing, the unsigned-to-signed conversion relies on signed integral overflow which is UB. Their names do not state the size of the datatype. They depend on 8-bit bytes and the presence of exact-size uint_ N _t. The input types are the same as the output types

I developing a network application and using socket APIs. I want to set sin6_addr byte order of sockaddr_in6 structure. For 16 bits or 32 bits variables, it is simple: Using htons or htonl: // IPv4 sockaddr_in addr; addr.sin_port = htons(123); addr.sin_addr.s_addr = htonl(123456); But for 128 bits variables, I dont know how to set byte order to network byte order: // IPv6 sockaddr_in6 addr; addr.sin6_port = htons(123); addr.sin6_addr.s6_addr = ??? // 16 bytes with network byte order but how to set? Some answers may be using htons for 8 times (2 * 8 = 16 bytes), or using htonl for 4 times (4 *