+
+Finally, results can be restricted to only messages within a
+particular time range, (based on the Date: header) with a syntax of:
+
+ <intial-timestamp>..<final-timestamp>
+
+Each timestamp is a number representing the number of seconds since
+1970\-01\-01 00:00:00 UTC. This is not the most convenient means of
+expressing date ranges, but until notmuch is fixed to accept a more
+convenient form, one can use the date program to construct
+timestamps. For example, with the bash shell the folowing syntax would
+specify a date range to return messages from 2009\-10\-01 until the
+current time:
+
+ $(date +%s \-d 2009\-10\-01)..$(date +%s)
+.SH ENVIRONMENT
+The following environment variables can be used to control the
+behavior of notmuch.
+.TP
+.B NOTMUCH_CONFIG
+Specifies the location of the notmuch configuration file. Notmuch will
+use ${HOME}/.notmuch\-config if this variable is not set.