#++
# NAME
#	pcre_table 5
# SUMMARY
#	format of Postfix PCRE tables
# SYNOPSIS
#	pcre:/etc/postfix/filename
# DESCRIPTION
#	The Postfix mail system uses optional tables for address
#	rewriting or mail routing. These tables are usually in
#	\fBdbm\fR or \fBdb\fR format. Alternatively, lookup tables
#	can be specified in Perl Compatible Regular Expression form.
#
#	To find out what types of lookup tables your Postfix system
#	supports use the \fBpostconf -m\fR command.
#
#	The general form of a PCRE table is:
# .IP "blanks and comments"
#	Blank lines are ignored, as are lines beginning with `#'.
# .IP "leading whitespace"
#	Lines that begin with whitespace continue the previous line.
# .IP "\fIpattern result\fR"
#	When \fIpattern\fR matches a search string, use the corresponding
#	\fIresult\fR. A line that starts with white space continues the
#	preceding line.
# .PP
#	Each pattern is a perl-like regular expression. The expression
#	delimiter can be any character, except whitespace or characters
#	that have special meaning (traditionally the forward slash is used).
#	The regular expression can contain whitespace.
#
#	By default, matching is case-insensitive, although following
#	the second slash with an `i' flag will reverse this. Other flags
#	are supported, but the only other useful one is `U', which makes
#	matching ungreedy (see PCRE documentation and source for more
#	info).
#
#	Each pattern is applied to the entire string being looked up.
#	Depending on the application, that string is an entire client
#	hostname, an entire client IP address, or an entire mail address.
#	Thus, no parent domain or parent network search is done, and
#	\fIuser@domain\fR mail addresses are not broken up into their
#	\fIuser\fR and \fIdomain\fR constituent parts, nor is \fIuser+foo\fR
#	broken up into \fIuser\fR and \fIfoo\fR.
#
#	Patterns are applied in the order as specified in the table, until a
#	pattern is found that matches the search string.
#
#	Substitution of sub-strings from the matched expression is
#	possible using the conventional perl syntax ($1, $2, etc.). The
#	macros in the replacement string may need to be written as ${n}
#	or $(n) if they aren't followed by whitespace.
# EXAMPLES
#	# Protect your outgoing majordomo exploders
#	/^(?!owner-)(.*)-outgoing@(my\.domain)$/    550 Use ${1}@${2} instead
#
#	# Bounce friend@whatever, except when whatever is our domain (you would
#	# be better just bouncing all friend@ mail - this is just an example).
#	/^friend@(?!my\.domain).*$/         550 Stick this in your pipe $0
#
#	# A multi-line entry. The text is sent as one line.
#	#
#	/^noddy@connect\.com\.au$/
#	\ 550 This user is a funny one. You really don't want to send mail to
#	\ them as it only makes their head spin.
# SEE ALSO
#	regexp_table(5) format of POSIX regular expression tables
# AUTHOR(S)
#	The PCRE table lookup code was originally written by:
#	Andrew McNamara
#	andrewm@connect.com.au
#	connect.com.au Pty. Ltd.
#	Level 3, 213 Miller St
#	North Sydney, NSW, Australia
#
#	Adopted and adapted by:
#	Wietse Venema
#	IBM T.J. Watson Research
#	P.O. Box 704
#	Yorktown Heights, NY 10598, USA
#--