Ordinarily, makemap will leave the ownership of the created file unchanged. That is, it will behave the same as any nonprivileged Unix program that creates files.

If the TrustedUser option (TrustedUser) is set in the sendmail configuration file, and if makemap was compiled with HASFCHOWN defined as 1, and if makemap is run by root, the output file will become owned by the TrustedUser option's user.

The makemap program finds the TrustedUser option by reading and parsing the sendmail program's configuration file (normally /etc/mail/sendmail.cf). If you want makemap to use a different configuration file, you can specify that different file with this -C switch, for example:

# makemap -C /etc/mail/sendmail.cf.new hash  outfile