man/sd-bus-container-append.c

#include <systemd/sd-bus.h>

int append_strings_to_message(sd_bus_message *m, const char *const *arr) {
  int r;

  r = sd_bus_message_open_container(m, 'a', "s");
  if (r < 0)
    return r;

  for (const char *s = *arr; *s; s++) {
    r = sd_bus_message_append(m, "s", s);
    if (r < 0)
      return r;
  }

  return sd_bus_message_close_container(m);
}