Updating through the command line and with market place took
1) Once you have packaged your extension in .zip file move it to a directory.
2) Download the validation script and extract it to the directory mentioned on the first step.
3) Run the following command.
php validate_m2_package.php <your_package_name.zip>
If no errors are there in the packaging and coding standards. No error will be visible on the console. If errors are there those will be listed on the console.
when doing this the following error showing up
"mytheme.zip" alternate folder structure is currently not supported
all of my 3 files in mytheme.zip