RE: deny share file read/write on Mac OS

FROM : shengjun_guan (???)
DATE : Fri Jan 11 03:13:24 2008

Thanks your reply.
Because i can't control how ProcessA open/write the file.That mean
ProcessA open the file without access lock ( O_EXLOCK ) , In my ProcessB
, also can open the file.


-----Original Message-----
From: Andrew Farmer [mailto:<email_removed>]
Sent: 2008/1/10 [¬P´Á¥|] ¤U¤È 05:17
To: shengjun_guan (ºÞÁn«T)
Cc: <email_removed>
Subject: Re: deny share file read/write on Mac OS

On 10 Jan 08, at 01:02, shengjun_guan (ºÞÁn«T) wrote:
>    I have one application(processA) is writting one file.
>    And , I create another application(processB) which want to know 
> that if processA are writting the file.
>    I know the Window MFC use CFile* file->open(fileName , 
> CFile::shareDenyWrite) , it can return FALSE if the file is being 
> written by processA.
>    On Mac OS side. i try some method to do it . but all false .
>    1.  use open(fileName , O_SHLOCK  , O_RDWR)
>    2.  use FSOpenFork
>    3.  NSFileManager
>
>    How can i do? Waiting for you help.Thanks a lot.


I found TN2037[1] in around a minute, which covers this stuff in 
excruciating detail. Please look for docs before you ask the mailing 
list!

[1]: http://developer.apple.com/technotes/tn/tn2037.html