puts.c\stdio\src - musl - musl - an implementation of the standard library for Linux-based systems

#include "stdio_impl.h"
int puts(const char *s)
{
	int r;
	FLOCK(stdout);
	r = -(fputs(s, stdout) < 0 || putc_unlocked('\n', stdout) < 0);
	FUNLOCK(stdout);
	return r;
}