[ <command>channel</command> <replaceable>channel_name</replaceable> {
( <command>file</command> <replaceable>path_name</replaceable>
[ <command>versions</command> ( <replaceable>number</replaceable> | <command>unlimited</command> ) ]
- [ <command>size</command> <replaceable>size spec</replaceable> ]
+ [ <command>size</command> <replaceable>size_spec</replaceable> ]
| <command>syslog</command> <replaceable>syslog_facility</replaceable>
| <command>stderr</command>
| <command>null</command> );