The board always boots the Linux image (from the SD card or from the SPI flash). When a sketch is uploaded it does not overwrite the flash like in the standard Arduino boards. In Galileo, the sketch runs as another service in the Yocto OS, it is stored in the sketch directory and the process can be seen with the command "ps" as "sketch.elf".
You can see more about communication between Arduino and Linux in IoT - Efficient communication between Arduino* and Linux native processes | Intel® Developer Zone
Thanks for your kind and insightful reply . BIG THANKS !
I have build kernel using BSP packages.After that boot bzImage,grub.efi,ext3 and coreminimal is created in /tmp/deploy folder.
I have copied four files to my SD card but i am unable to boot.Can anyone tell how to make partitions in SD card and copy files created in /tmp/deploy folder??
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