cal.txt

date = getdate(time());
t = getdate(mktime(0, 0, 0, date.mon, 1, date.year));
offset = t.wday;

if (date.mon == 12) {
	date.year += 1;
	date.mon = 1;
}
else {
	date.mon += 1;
}
t = getdate(mktime(0, 0, 0, date.mon, 1, date.year)-1);
count = t.mday;

echo("\x1b[2J\x1b[H"); // 画面消去
for (i=0; i<offset; i++) {
	echo("   ");
}

for (i=1; i<=count; i++) {
	echo(sprintf("%2d%s", i, (++offset%7==0)?"\n":" "));
}
if (offset % 7 != 0) {
	echo("\n");
}