Re: [Help-glpk] Re: libglpk0: excessive install dependencies

[Xypron]

Hello Vijay,

I am currently implementing using dynamic load libraries for linux.

My idea is to try to load MySQL and iODBC in mpl_initialize and to 
unload the libraries in mpl_terminate. I want to use library ltdl to 
gain support for most Linux like operating systems. I plan to use #ifdef 
WIN32 to use loadlibrary instead of lt_dlopenext, etc. when compiling 
with windows.

Best regards

Xypron




vijay patil wrote:
> On Thu, Mar 13, 2008 at 11:02 PM, vijay patil <address@hidden 
> <mailto:address@hidden>> wrote:
>
>     It would be nice to have this change (i.e. explicitly loading the
>     dynamic library/shared object related to table feature in
>     MathProg) work on MS Windows.
>
>     I ported example on page http://linux.die.net/man/3/dlopen to
>     windows. We will need to use ifdefs at come places (loading,
>     unloading, and getting function address), but actual function
>     invocation is OS independent. I have tested program below on
>     Windows XP and it works as expected.
>
>
> I forgot to post to reference links (for code) yesterday, here :
>
> About Dynamic-Link Libraries
> http://msdn2.microsoft.com/en-us/library/ms681914(VS.85).aspx 
> <http://msdn2.microsoft.com/en-us/library/ms681914%28VS.85%29.aspx>
>
> LoadLibrary Function
> http://msdn2.microsoft.com/en-us/library/ms684175(VS.85).aspx 
> <http://msdn2.microsoft.com/en-us/library/ms684175%28VS.85%29.aspx>
>
> -------------------------------
> Example just demonstrates how to invoke simple function (like cos). I 
> wonder how to define a pointer to a structure (that is) defined in 
> dynamic lib/shared object.
>
> For example, in file glpsql.c (in libglpk-4.27) we have:
>
>    MYSQL           *con;   //connection
>    MYSQL_RES       *res;    //result
>
> These pointers are used to store return values of MySQL functions like 
> mysql_init. Structures MYSQL and MYSQL_RES are defined in 
> libmySQL.dll. I think those pointers (con, res) have to be converted 
> into void pointers, unless there is better way. I tried some simple C 
> examples using void*, and seems to work.
>
> --
> Vijay Patil