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Wireshark-dev: Re: [Wireshark-dev] Problems with bitmasks and 64 bit values

From: Guy Harris <guy@xxxxxxxxxxxx>
Date: Sun, 30 Oct 2016 14:54:12 -0700
On Oct 30, 2016, at 2:39 PM, Thomas Wiens <th.wiens@xxxxxx> wrote:

> 1) It seems to be impossible to decode a value inside the bitmask as
> signed integer
> 
> The "Error code" value should be 16 bit signed integer.

But you said it was a 64-bit unsigned integer:

 { "Error code", "s7comm-plus.returnvalue.errorcode", FT_UINT64, BASE_HEX, NULL, 0x000000000000ffff,
   NULL, HFILL }},

Try saying it's a 16-bit signed integer - FT_INT16 - instead.

Note, however, that we don't support showing negative octal or hex values; if you want it to show up as a signed value, display it with BASE_DEC or BASE_HEX_DEC.