This is the mail archive of the cygwin@cygwin.com mailing list for the Cygwin project.


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]

Re: AW: DLL function with string result?



----- Original Message -----
From: "Christian Lescher" <christian@lescher.de>
To: "Larry Hall (RFK Partners, Inc)" <lhall@rfk.com>
Cc: "Lescher Christian" <christian.lescher@icn.siemens.de>; "'Andrew
Markebo'" <flognat@flognat.myip.org>; "Troy Noble"
<troy.noble@channelpoint.com>; <cygwin@cygwin.com>
Sent: Saturday, April 21, 2001 4:12 AM
Subject: Re: AW: DLL function with string result?


> I found that in windowsx.h of cygwin/gcc there are the following
functions defined:
>
> #define GlobalAllocPtr(flags,cb)
(GlobalLock(GlobalAlloc((flags),(cb))))
> #define GlobalFreePtr(lp)
(GlobalUnlockPtr(lp),(BOOL)GlobalFree(GlobalPtrHandle(lp)))
>
> May these functions also be used for copying a string? How must they
be used? (Maybe this works also for string > 64 KB?!)
> Is this also a way for interworking of Borland and Visual?

I'd like to point out that /dec/clipboard in cygwin uses standard
malloc, which IIRC strdup does as well. /dev/clipboard handles
multi-megabyte copy and pastes.

There are _no_ issues that I know of with strings > 64Kb in cygwin.

64Kb is the largest size of a single segment in x86 processors running
in real mode. Some of the early win9x series microsoft class libraries &
utilities had a 64Kb limit on various things  because (As I understand
it) they were not fully ported to protected mode when win95 came out. If
you are seeing 64Kb issues I suggest you do the following.

In your compiler environment (ie if your prog is in Visual, your library
in Cygwin then I mean in visual), write a test case. If that works then
it's either a interop issue or a problem with the library compiler.

Rob


> Christian
>
> | char*
> | mallocAndStrCpy (const char* srcStr) {
> |    if (srcStr == NULL)
> |       return NULL;
> |    return strdup(srcStr);
> | }
>
>
>
>
> --
> Want to unsubscribe from this list?
> Check out: http://cygwin.com/ml/#unsubscribe-simple
>
>


--
Want to unsubscribe from this list?
Check out: http://cygwin.com/ml/#unsubscribe-simple


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]