#include <ctype.h> /* isdigit(3) */
#include <stdlib.h> /* atoi(3) */
#include <sysexits.h> /* EX_USAGE */
#include <unistd.h> /* sleep(3) */
#include "libio.h"

static char *program_name = "sleep";

int main(int argc, char **argv){
	int s;
	if(argc != 2){
usage:		write(2, "Usage: ", 7);
		fdprint(2, argv[0] == NULL ? program_name : argv[0]);
		write(2, " [seconds]\n", 11);
		return EX_USAGE;
	}
	s = parse_uint(argv[1]);
	while(isdigit(*argv[1]))
		++argv[1];
	if(*argv[1] != '\0')
		goto usage;
	while(s > 0)
		s = sleep(s);
	return s;
}