# $EPIC: which_function.txt,v 1.3 2007/03/02 02:32:04 jnelson Exp $
======Synopsis:======
$__which__(%%<file>%% [<dir>[:<dir> ...]])

======Technical:======
The %%<file>%% argument is a [[what is a word|dword]], which is different
from most functions.

This function returns the full pathname of the specified filename.  The
function will search the client's current [[set load path|LOAD_PATH]] for the
file.  In addition, a list of colon-delimited directories may be specified,
which will be searched if the file is not found in the [[set load
path|LOAD_PATH]].

======Practical:======
This function tries to find the location of a particular file.  This makes it
suitable for [[LOAD]] and [[STUB]] commands, allowing a file to be loaded, even
if its exact location is not known.

======Returns:======
the canonical path of the file, or nothing if it isn't found

======Examples:======
<file>
$which(some_file)           shows full path of file
$which(does_not_exist)      returns nothing, file dies not exist
$which(some_file /bin)      search in /bin for some_file too
</file>