This message was posted on behalf of Intel Corporation
There are several options and languages available to program the Edison. You can use an IDE and you can also use shell. More information on the IDEs can be found here https://software.intel.com/en-us/iot/software/ide .
In shell, if you type echo $SHELL you’ll see /bin/sh as a result. I’m not familiar with the mycshrc file, but you can create .sh files from the terminal using something like: vi mycshrc.sh