At 17:18 31/05/2007, you wrote:
>On 5/31/07, Eduardo Morras <[EMAIL PROTECTED]> wrote:
>>At 23:25 30/05/2007, you wrote:
>>>Setting and reading individual bytes (u8 in sqlite-speak) are not
>>>threadsafe either. Only reading/setting entire entire words
>>>are threadsafe on most architectures.
>>
>>Using a uint32 for store the flags is threadsafe. There are less than 32
>>true/false values and read/set is simple. I see no difference doing
>>
>>if (uint8==0){ // read/test bit
>>uint8=1; // set bit
>>whatever more
>>}
>
>Not atomic, so not thread-safe.
>You have a race condition waiting to happen.
>
>>and
>>
>>if (uint32&&MASK){ // read/test bit
>>uint32&&=MASK; // set bit
>>whatever
>>}
>
>Also not atomic, so not thread-safe.
I think i have not explained too well. I have wanted to point that if you can
modify/set 8 or 9 values atomically/thread-safe you can do it with one 32 bit
flag value.
------------------------------------------------------------------------------------------------------------
Usuario de FreeBSD+Xfce, OpenOffice y muchos mas OSS.
Microsoft declara que el OSS viola 235 patentes. Por favor, DENUNCIAME.
-----------------------------------------------------------------------------
To unsubscribe, send email to [EMAIL PROTECTED]
-----------------------------------------------------------------------------
