Initialize an IPv6 routing header
#include <netinet/in.h>
struct cmsghdr * inet6_rthdr_init(void *bp,
int type);
This function initializes the buffer pointed to by bp to contain a cmsghdr structure followed by a Routing header of the specified type. The cmsg_len member of the cmsghdr structure is initialized to the size of the structure plus the amount of space required by the Routing header.
The cmsg_level and cmsg_type members are also initialized as required.
You must allocate the buffer before calling this function. To determine the size of the buffer, call inet6_rthdr_space().
Based on:
A pointer to the cmsghdr structure, which you'll pass to other functions (and used as the first argument to list functions), or NULL if an error occurred.
| Safety: | |
|---|---|
| Cancellation point | No |
| Interrupt handler | No |
| Signal handler | Yes |
| Thread | Yes |