# $EPIC: getserial.txt,v 1.2 2007/02/19 03:20:46 jnelson Exp $
======Synopsis:======
$[[getserial]](HOOK + //number//)
$[[getserial]](HOOK - //number//)

======Description:======
This function allows you to retrieve a serial number that is guaranteed not
to be in use.  At the time of this writing, the only serial number type that
is supported is for [[on]] hooks, although more types are expected in the
future.

The first form returns the first serial number that is later than //number// 
that is not in use by any [[on]] hook of any type, whatsoever.  It is 
absolutely guaranteed //at the time you call getserial// that you can use 
this serial number with no interference to or from any other script that 
also uses [[getserial]].

The second form returns the first serial number that is smaller than //number//
that is not in use by any [[on]] hook of any type, whatsoever.

The //number// value is optional; the default value of //number// is 0.

This feature is closely related to the ability to specify a bare //+// or
//-// as the serial number in an [[on]].

======History:======
This function was written by wd and first appeared in EPIC4-1.1.8.