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Subject: Can open() from console app, not from dll
From: Massimiliano Mirra <mmirra AT libero DOT it>
Date: Tue, 01 Apr 2003 22:44:21 +0200
Message-ID: <874r5ine1m.fsf@prism.localnet>
User-Agent: Gnus/5.090016 (Oort Gnus v0.16) Emacs/21.2
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Content-Type: text/plain; charset=us-ascii


I am able to open a file and write into it from a console application,
but the same fails when done from within a function that is stored in
a DLL and called from a Visual Basic application.

This is the console app:

,----
| #include <fcntl.h>
| 
| int main (int argc, char * argv[]) {
|   int fd;
|   char *msg = "Hello, world\n";
| 
|   fd = open ("file.txt", O_CREAT | O_RDWR);
|   if (fd == -1) {
|     perror ("open()");
|     exit (-1);
|   }
| 
|   write (fd, msg, strlen (msg));
| }
`----

And this is the source of foo.dll:

,----
| #include <fcntl.h>
| 
| int WINAPI DllMain (HINSTANCE H, DWORD d, PVOID p) {
|   return TRUE;
| }
| 
| int OpenSomething () {
|   int fd;
| 
|   char *msg = "Hello, world\n";
| 
|   fd = open ("file.txt", O_CREAT | O_RDWR);
|   if (fd == -1) {
|     perror ("open()");
|     exit (-1);
|   }
| 
|   write (fd, msg, strlen (msg));
|   return TRUE;
| }
`----

The DLL is compiled with (found in the archives):

$(LD) --dll --subsystem windows -e _DllMain AT 12 -o jnk --base-file foo.base \
  foo.o -L $(LIB)/w32api -luser32 -c
$(DLLTOOL) --dllname foo.dll --base-file foo.base --def foo.def --output-lib \
  foo.a --output-exp foo.exp
$(LD) --dll --subsystem windows -e _DllMain AT 12 -o foo.dll foo.o -L \
  $(LIB)/w32api -luser32 -c foo.exp
rm jnk foo.base foo.exp


When run under Wine, the VB app hangs on the open() and causes this:

err:ntdll:RtlpWaitForCriticalSection section 0x610d1ef8 "?" wait timed out,
  retrying (60 sec) tid=080771f8

When run on a w98 box, it crashes on the open() with an ``Invalid Page
Fault'' (sort of, I'm translating from Italian).

The console application works just fine both on the box and under
Wine.  What am I missing?


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