! This does the same as PrintAnything, but the output is sent to a
! byte array in memory. The first two arguments must be the array
! address and length; the following arguments are interpreted as
! for PrintAnything. The return value is the number of characters
! output.
! If the output is longer than the array length given, the extra
! characters are discarded, so the array does not overflow.
! (However, the return value is the total length of the output,
! including discarded characters.)

[ PrintAnyToArray _vararg_count arr arrlen str oldstr len;
    @copy sp arr;
    @copy sp arrlen;
    _vararg_count = _vararg_count - 2;

    oldstr = glk($0048); ! stream_get_current
    str = glk($0043, arr, arrlen, 1, 0); ! stream_open_memory
    if (str == 0) return 0;

    glk($0047, str); ! stream_set_current

    @call PrintAnything _vararg_count 0;

    glk($0047, oldstr); ! stream_set_current
    @copy $ffffffff sp;
    @copy str sp;
    @glk $0044 2 0; ! stream_close
    @copy sp len;
    @copy sp 0;

    return len;
];