+It is similar in spirit to other tools such as mu or notmuch, but is
+overall simpler.
+
+.SH "OPTIONS"
+.TP
+\fB-h\fR, \fB--help\fR
+display help and exit
+.TP
+\fB-v\fR, \fB--version\fR
+print the version number
+.TP
+\fB-q\fR, \fB--quiet\fR
+do not write information during the search
+.TP
+\fB-t\fR, \fB--use-leading-time\fR
+use the time stamp from the leading line of each mail and not the
+Date: field
+.TP
+\fB-p <db filename pattern>\fR, \fB--db-pattern <db filename pattern>\fR
+set the db filename pattern for recursive search
+.TP
+\fB-r <db root path>\fR, \fB--db-root <db root path>\fR
+set the db root path for recursive search
+.TP
+\fB-l <db filename list>\fR, \fB--db-list <db filename list>\fR
+set the semicolon-separated list of db files for search
+.TP
+\fB-m <mbox filename pattern>\fR, \fB--mbox-pattern <mbox filename pattern>\fR
+set the mbox filename pattern for recursive search
+.TP
+\fB-s <search pattern>\fR, \fB--search <search pattern>\fR search for
+matching mails in the db file. Multiple search requests can be
+combined, and only mails fulfilling all of them will be extracted.
+.TP
+\fB-d <db filename>\fR, \fB--db-file-generate <db filename>\fR
+set the db filename for indexing
+.TP
+\fB-i\fR, \fB--index\fR
+index mails in the mailboxes located recursively anywhere in the
+directories following the options on the command lines
+.TP
+\fB-o <output filename>\fR, \fB--output <output filename>\fR set the
+result mbox filename. If it is not set, the standard output is used
+.TP
+\fB-a <search key>\fR, \fB--default-search <search key>\fR
+set the default search key. If a search request is not understood,
+it is interpreted as the regexp with this default search key
+
+.SH "ENVIRONMENT VARIABLES"
+
+.TP
+\fBMYMAIL_DB_PATTERN\fR
+defaut value for the --db-pattern argument
+.TP
+\fBMYMAIL_DB_ROOT\fR
+defaut value for the --db-root argument
+.TP
+\fBMYMAIL_DB_LIST\fR
+defaut value for the --db-list argument
+.TP
+\fBMYMAIL_DB_FILE\fR
+defaut value for the --db-file argument