Le jeu 12/08/2004 Ã 14:19, bertrand marquis a Ãcrit : > Le jeu 12/08/2004 Ã 14:03, bertrand marquis a Ãcrit : > > Le jeu 12/08/2004 Ã 12:44, Corinna Vinschen a Ãcrit : > > > On Aug 12 12:13, bertrand marquis wrote: > > > > In fact i wasn't using the SHM_RNd flag. > > > > > > > > In details here is what i do: > > > > > > > > - get a shared segment of with size= SIZE (SIZE multiple of SHMLBA) > > > > - attach the segment without specifying address and storing the result > > > > in beginaddress > > > > - attach the segment again specifying the address: endposition= > > > > beginaddress + SIZE > > > > > > > > without SHM_RND in the second shmat i've got the error : invalid > > > > argument > > > > > > > > now that i specifie SHM_RND in the flag i have the error: value to large > > > > for defined type .... > > > > > > > > any idea ? > > > > > > Nope. Not without knowing the actual values. An strace output of > > > the affected calls would be good. Even better, create a simple testcase > > > which allows to reproduce the behaviour. Just the minimum of necessary > > > code. > > > > > > > > > Corinna > > > > > > Ok, > > > > i have made a minimum program showing the problem. > > You can try specifying or not SHM_RND in the second shmat, without i > > have INvalid argument error and with i have value too large for defined > > data type. > > > > > > thanks > > bertrand > > > > ______________________________________________________________________ > Hello > > Running some tests it seems that specifying an adress is not the problem > because if i give an adress in the first shmat it is running well as > long as this adress is free. > In fact the problem is only when specifying an adress for mapping the > same segment twice and only if we specifie the adress the second time. > > i hope it could help or give an idea to someone. > > bertrand > > > -- > Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple > Problem reports: http://cygwin.com/problems.html > Documentation: http://cygwin.com/docs.html > FAQ: http://cygwin.com/faq/ >
Hello an other time, Ok i perhaps find a solution or a beginning of solution: the getpagesize() function return a value of 4096 for the page size and it seems that shmat need the address to be aligned on a multiple of SHMLBA (655539), if instead of using getpagesize value to round the size i use the value of SHMLBA i can run the test program without any problem. the thing is that this doesn't append under linux. In fact under linux SHMLBA=getpagesize=4096 so the program run perfectly without any problem. Perhaps the cygwin release of getpagesize should output also SHMLBA ? bertrand -- Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple Problem reports: http://cygwin.com/problems.html Documentation: http://cygwin.com/docs.html FAQ: http://cygwin.com/faq/