Sending a buffer over network unix

send-sendto-sendmsg.c

#include <sys/types.h>
#include <sys/socket.h>

ssize_t send(int sockfd, const void *buf, size_t len, int flags);

ssize_t sendto(int sockfd, const void *buf, size_t len, int flags,
              const struct sockaddr *dest_addr, socklen_t addrlen);

ssize_t sendmsg(int sockfd, const struct msghdr *msg, int flags);