int result = vasprintf(strp, fmt, ap);
if(result < 0) {
fprintf(stderr, "vasprintf() failed: %s\n", strerror(errno));
exit(xalloc_exit_failure);
}
int result = vasprintf(strp, fmt, ap);
if(result < 0) {
fprintf(stderr, "vasprintf() failed: %s\n", strerror(errno));
exit(xalloc_exit_failure);
}