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(am-utils.info)NFS-Link Filesystem

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NFS-Link Filesystem (`nfsl')
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   The "nfsl" (`type:=nfsl') filesystem type is a combination of two
others: `link' and `nfs'.  If the local host name is equal to the value
of `${rhost}', or if the target pathname listed in `${fs}' exists,
`nfsl' will behave exactly as `type:=link', and refer to the target as
a symbolic link.  If the local host name is not equal to the value of
`${rhost}', or if the target of the link does not exist, Amd will treat
it as `type:=nfs', and will mount a remote pathname for it.

   The `nfsl' filesystem type is particularly useful as a shorthand for
the more cumbersome and yet one of the most popular Amd entries.  For
example, you can simplify all map entries that look like:

     zing    -fs:=/n/shekel/u/zing \
             host!=shekel;type:=nfs;rhost:=shekel;rfs:=${fs} \
             host==shekel;type:=link

   or

     zing    -fs:=/n/shekel/u/zing \
             exists(${fs});type:=link \
             !exists(${fs});type:=nfs;rhost:=shekel;rfs:=${fs}

   into a shorter form

     zing    type:=nfsl;fs:=/n/shekel/u/zing;rhost:=shekel;rfs:=${fs}

   Not just does it make the maps smaller and simpler, but it avoids
possible mistakes that often happen when forgetting to set up the two
entries (one for `type:=nfs' and the other for `type:=link') necessary
to perform transparent mounts of existing or remote mounts.