The name

The name portion of the K configuration command immediately follows the K. Whitespace between the K and the name is optional:

K name type argsoptional whitespace

The name must begin with a letter or digit and can contain only letters, digits, and the underscore character:

K local_hosts      ← good
K $andcents        ← bad

The case of the letters in name does not matter. All names are converted to lowercase before they are stored:

K LOCAL_Hosts
K local_hosts      ← the same

If you begin a name with a bad character, the following error will be printed and that K line will be ignored:

configfile: line num: readcf: config K line: no map name

If a bad character appears in the middle of a name, the part preceding the bad character will be taken as the name, and the part following the bad character will be taken as the type. For example, the name me@home will produce this error:

configfile: line num: readcf: map me: class home  not available

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