micheal..you are telling that read() function will do the same as the mmap() does..but the read() will read the data from the memory i think....is this ,,ap() is also doing the same one?if yes....how its actually the data (when capturing the video) was stored in memory....? --- On Fri, 23/1/09, Michael Williamson <[email protected]> wrote: From: Michael Williamson <[email protected]> Subject: Re: mmap() To: [email protected] Date: Friday, 23 January, 2009, 10:28 PM
--- On Fri, 1/23/09, niamathullah sharief <[email protected]> wrote: > From: niamathullah sharief <[email protected]> > Subject: mmap() > To: "video4linux list" <[email protected]>, "Kernel newbies" <[email protected]>, "micheal williams" <[email protected]> > Date: Friday, January 23, 2009, 7:14 AM > Hello, Actually what is mmap()?why it used?shall we > write the program without that function? The mmap() function makes the memory containing the picture pixel data available to the program. The alternative is to use the read() function, to get the picture pixel data. I do not have a program that does it that way. It is possible to get picture pixel data from a camera from the shell prompt like this: # head -c 304128 /dev/video0 > pict.raw That does the same things as open() and read() functions do using a 'C' program. -Mike Add more friends to your messenger and enjoy! Go to http://messenger.yahoo.com/invite/
