How to create subfolder on mailbox from command line

On a CentOS 7 machine running Postfix and Dovecot how could I create subfolder named 'Bulk' on a inbox trough command line?

I thought to use the maildirmake command but this returns "maildirmake command not found".

I've ended up using the doveadm mailbox create command to create additional folders in mailboxes. It creates the necessary cur, tmp and new subdirectories.

A Maildir is simply a directory that has the cur, tmp and new subdirectories.

IMAP Folders are usually simply subdirectories inside the main Maildir whose names start with a period, and which in turn are themselves Maildirs. They must also contain a zero-length file named maildirfolder. See http://www.courier-mta.org/maildir.html

That makes it trivial to create new folders with the mkdir command.

mkdir /path/to/Maildir/.Bulk
mkdir /path/to/Maildir/.Bulk/new
mkdir /path/to/Maildir/.Bulk/tmp
mkdir /path/to/Maildir/.Bulk/cur
touch /path/to/Maildir/.Bulk/maildirfolder

By making use of shell expansion you can reduce that to a single mkdir command:

mkdir -p /path/to/Maildir/.Bulk/{cur,tmp,new} 
touch /path/to/Maildir/.Bulk/maildirfolder

An IMAP subfolder is not nested in the parents Maildir folder, but represented as a directory on the some levels as the parent, with a name that starts with a leading dot . , the name of the parent folder, a second dot . and then the name of the sub folder, i.e. a subfolder "Serverfault" in you "Bulk" folder may look like:

mkdir -p /path/to/Maildir/.Bulk.Serverfault/{cur,tmp,new}
touch /path/to/Maildir/.Bulk.Serverfault/maildirfolder