

individual clauses are as follows:

[field name] [operator] [operand] 


clauses may be combined as follows

[clause] & [clause]
must satisfy both requirements

[clause] | [clause] 
can satisfy either clause

with no paretheses, | is evaluated before &

in future versions order of operations may forced by paretheses, but
parentheses make the operation harder to read and should only be 
used in cases where the meaning of the uri would be changed by them.


Possible field names are file attributes.
the following fields are currently defined:
root		specifies a default location for the search
file_name       specifies the name of files
directory_name  specifies the name of directory in the file's path
mod_time	specifies the last time a file was modified
owner           the owner of the file
group           the group the file belongs to 
permissions     the file's permissions
size            the file's size
mime_type       the file's mime type

possible operations are as follows
equals          specifies exact equivalence.
	        for root, file_name, directory_name, and mime_type this is string equivalence
                for all other fields this is a numerical equivalence
greater_than    is only defined for numerical fields
less_than       is only defined for numerical fields
regexp_matches  is only defined for string fields (see equals)

possible operands should be valid uri text, and if not, appropriate characters
should be quoted.








Examples:

search: root "file:///" &  root "file:///mnt", 

search: root "file://" & mime_type regexp_matches application | mime_type regexp_matches application
