int send_buffer(int, const char *);
int send_bin_buffer(int, const char *, size_t);
__printf_2_3 int send_va_buffer(int fd, const char *fmt, ...);
int send_buffer(int, const char *);
int send_bin_buffer(int, const char *, size_t);
__printf_2_3 int send_va_buffer(int fd, const char *fmt, ...);