You wonder how to test and use your sieve scripts locally on your mailserver?

dry-run 

sieve-filter -v -C -u user@domain.tld /var/vmail/domain.tld/user/sieve/scriptname.sieve 'INBOX'

execute (note the additional -e -W) 

sieve-filter -v -C -e -W -u user@domain.tld /var/vmail/domain.tld/user/sieve/scriptname.sieve 'INBOX'