Store a filename in a variable minus the extension

Use bash parameter expansion:

zip_file="${filename}"
new_name="${zip_file%.*}"   

• new_name will contain the name test if the zip_file has test.zip

• If the zip_file has test.foo.zip, new_name will have test.foo, if you want only test out of test.foo.zip use:

  new_name="${zip_file%%.*}"