The editmap program must be run with one of three mandatory command-line switches. This -x switch is one of those three.

The -x command-line switch tells editmap to open the database file in read/write mode, to look up the key, and, if found, to delete the key and its value from the database:

% editmap -x  dbtype dbfile sought-key  

If the dbfile lacks read/write permission, the following error will print and editmap will exit with an EX_IOERR (EX_IOERR) exit value.

editmap: error opening type dbtype map dbfile: Permission denied

If the sought-key is found, it and its value are silently deleted from the database. If the sought-key is not found, editmap prints the following error and exits with an EX_UNAVAILABLE (EX_UNAVAILABLE) exit value:

editmap: couldn't find key sought-key in map dbfile

If you get this error when reading aliases-style database files, consider adding the -N command-line switch.