呵呵, 很像在 bash 中按 Ctrl+u :

int getdata(...)
{
    //...
+       if (ch == Ctrl('U')) {
+           if (curr == 0)
+               continue;
+           clen = 0;
+           curr = 0;
+           move(y, x);
+           buf[0] = '\0';
+           clrtoeol();
+           continue;
+       }

        if (ch == KEY_DEL) {
            if (curr >= clen) {
                curr = clen;
    //...
}
--