char *str;
size_t len, slen;
len = strlen(but->editstr);
slen = ime->composite_len;
str = MEM_mallocN(sizeof(char) * (slen + len + 1), "drawstr edit buffer");
memcpy(str, but->editstr, sizeof(char) * but->pos);
memcpy(str + but->pos, ime->composite, sizeof(char) * slen);
memcpy(str + but->pos + slen, but->editstr + but->pos, sizeof(char) + (len - but->pos));
str[len + slen] = '\0';
drawstr = drawstr_edit = str;