puts() adds a newline at the end. gcc will happily turn printf("%s\n", str) into puts(str), though. I've never tested to see if printf("%s", str) becomes the e

puts() adds a newline at the end. gcc will happily turn printf("%s\n", str) into puts(str), though. I've never tested to see if printf("%s", str) becomes the equivalent fputs(str, stdout)