The remaining sections of this chapter describe more advanced
autofs features and topics.
Autofs and Metacharacters
Autofs recognizes some characters as having a special meaning.
Some characters are used for substitutions, and some characters are used to
protect other characters from the autofs map parser.
If you have a map with many
subdirectories specified, as in the following, consider using string substitutions.
You can use the ampersand character (&) to substitute
the key wherever the key appears. If you use the ampersand, the previous map
changes to the following:
You could also use key substitutions in a direct map, in situations
such as the following:
You can also simplify the entry further as follows:
Notice that the ampersand substitution uses the whole key string. Therefore,
if the key in a direct map starts with a / (as it should),
the slash is included in the substitution. Consequently, for example, you
could not do the following:
The reason is that autofs would interpret the example as the following:
You can use the universal substitute character,
the asterisk (*), to match any key. You could mount the /export file system from all hosts through this map entry.
Each ampersand is substituted by the value of any given key. Autofs
interprets the asterisk as an end-of-file character.
Autofs and Special Characters
If you have a map entry that contains special characters,
you might have to mount directories that have names that confuse the autofs
map parser. The autofs parser is sensitive to names that contain colons, commas,
and spaces, for example. These names should be enclosed in double-quotes,
as in the following:
/vms -ro vmsserver: - - - "rc0:dk1 - "
/mac -ro gator:/ - "Mr Disk - "