Userspace/apps/base/echo/echo.c

#include <stdio.h>

int main(int argc, char *argv[])
{
	if (argc == 1)
	{
		printf("Usage: echo [args]\n");
		return 0;
	}

	for (int i = 1; i < argc; i++)
		printf("%s ", argv[i]);
	printf("\n");
	return 0;
}