2 #include <sys/socket.h>
7 int sendmmsg(int fd, struct mmsghdr *msgvec, unsigned int vlen, unsigned int flags)
10 /* Can't use the syscall directly because the kernel has the wrong
11 * idea for the types of msg_iovlen, msg_controllen, and cmsg_len,
12 * and the cmsg blocks cannot be modified in-place. */
14 if (vlen > IOV_MAX) vlen = IOV_MAX; /* This matches the kernel. */
15 for (i=0; i<vlen; i++) {
16 /* As an unfortunate inconsistency, the sendmmsg API uses
17 * unsigned int for the resulting msg_len, despite sendmsg
18 * returning ssize_t. However Linux limits the total bytes
19 * sent by sendmsg to INT_MAX, so the assignment is safe. */
20 ssize_t r = sendmsg(fd, &msgvec[i].msg_hdr, flags);
21 if (r < 0) goto error;
22 msgvec[i].msg_len = r;
27 return syscall_cp(SYS_sendmmsg, fd, msgvec, vlen, flags);