puts() in C: Writing a String to stdout with an Automatic Newline

puts(str) writes the string to stdout and appends a newline. That is the entire function. It is equivalent to printf("%s\n", str) but shorter and marginally faster because it skips format parsing. It takes exactly one argument. No format specifiers. No variadic behavior. If you just need to print a line of text, puts is the cleanest option.

puts returns a non-negative value on success and EOF on failure. It reads from the string until the null terminator, writes everything, then writes \n. If your string already ends with \n, you get a blank line. Unlike fputs, you cannot suppress the newline. If you need that control, use fputs with stdout.

puts is a convenience. Use it for simple messages. Reach for printf or fputs the moment you need formatting or newline control. Next: tmpfile, which creates a temporary file that deletes itself when closed.