#++
# NAME
#	pcre_table 5
# SUMMARY
#	format of Postfix PCRE tables
# SYNOPSIS
#	\fBpcre:/etc/postfix/\fIfilename\fR
#
#	\fBpostmap -q "\fIstring\fB" pcre:/etc/postfix/\fIfilename\fR
#
#	\fBpostmap -q - pcre:/etc/postfix/\fIfilename\fR <\fIinputfile\fR
# 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.
#
#	To test lookup tables, use the \fBpostmap\fR command as
#	described in the SYNOPSIS above.
#
#	The general form of a PCRE table is:
# .IP "\fB/\fIpattern\fB/\fIflags result\fR"
#	When \fIpattern\fR matches a search string, use the corresponding
#	\fIresult\fR value.
# .IP "blank lines and comments"
#	Empty lines and whitespace-only lines are ignored, as
#	are lines whose first non-whitespace character is a `#'.
# .IP "multi-line text"
#	A logical line starts with non-whitespace text. A line that
#	starts with whitespace continues a logical line.
# .IP "\fBif /\fIpattern\fB/\fIflags\fR"
# .IP "\fBendif\fR"
#	Examine the lines between \fBif\fR..\fBendif\fR only if
#	\fIpattern\fR matches. The \fBif\fR..\fBendif\fR can nest.
#	Do not prepend whitespace to patterns inside \fBif\fR..\fBendif\fR.
# .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, and newlines are not
#	treated as special characters. The behavior is controlled by flags,
#	which are toggled by appending one or more of the following
#	characters after the pattern:
# .IP "\fBi\fR (default: on)"
#	Toggles the case sensitivity flag. By default, matching is case
#	insensitive.
# .IP "\fBm\fR (default: off)"
#	Toggles the PCRE_MULTILINE flag. When this flag is on, the \fB^\fR
#	and \fB$\fR metacharacters match immediately after and immediately
#	before a newline character, respectively, in addition to
#	matching at the start and end of the subject string.
# .IP "\fBs\fR (default: on)"
#	Toggles the PCRE_DOTALL flag. When this flag is on, the \fB.\fR
#	metacharacter matches the newline character. With
#	Postfix versions prior to 20020528, The flag is off by
#	default, which is inconvenient for multi-line message header
#	matching.
# .IP "\fBx\fR (default: off)"
#	Toggles the pcre extended flag. When this flag is on, whitespace
#	in the pattern (other than in a character class) and
#	characters between a \fB#\fR outside a character class and
#	the next newline character are ignored. An escaping backslash
#	can be used to include a whitespace or \fB#\fR character
#	as part of the pattern.
# .IP "\fBA\fR (default: off)"
#       Toggles the PCRE_ANCHORED flag.  When this flag is on,
#	the pattern is forced to be "anchored", that is, it is
#	constrained to match only at the start of the string which
#	is being searched (the "subject string"). This effect can
#	also be achieved by appropriate constructs in the pattern
#	itself.
# .IP "\fBE\fR (default: off)"
#	Toggles the PCRE_DOLLAR_ENDONLY flag. When this flag is on,
#	a \fB$\fR metacharacter in the pattern matches only at the
#	end of the subject string. Without this flag, a dollar also
#	matches immediately before the final character if it is a
#	newline character (but not before any other newline
#	characters). This flag is ignored if PCRE_MULTILINE
#	flag is set.
# .IP "\fBU\fR (default: off)"
#	Toggles the ungreedy matching flag.  When this flag is on,
#	the pattern matching engine inverts the "greediness" of
#	the quantifiers so that they are not greedy by default,
#	but become greedy if followed by "?".  This flag can also
#	set by a (?U) modifier within the pattern.
# .IP "\fBX\fR (default: off)"
#       Toggles the PCRE_EXTRA flag.
#	When this flag is on, any backslash in a pattern that is
#	followed by a letter that has no special meaning causes an
#	error, thus reserving these combinations for future expansion.
# .PP
#	Each pattern is applied to the entire lookup key string.
#	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 substrings from the matched expression into the result
#	string is possible using the conventional perl syntax ($1, $2, etc.).
#	The macros in the result string may need to be written as ${n}
#	or $(n) if they aren't followed by whitespace.
# EXAMPLE SMTPD ACCESS MAP
#	# Protect your outgoing majordomo exploders
#	/^(?!owner-)(.*)-outgoing@(.*)/ 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 $0
#
#	# A multi-line entry. The text is sent as one line.
#	#
#	/^noddy@my\\.domain$/
#	\ 550 This user is a funny one. You really don't want to send mail to
#	\ them as it only makes their head spin.
# EXAMPLE HEADER FILTER MAP
#	/^Subject: make money fast/     REJECT
#	/^To: friend@public\\.com/	 REJECT
# EXAMPLE BODY FILTER MAP
#	# First skip over base 64 encoded text to save CPU cycles.
#	# Requires PCRE version 3.
#	~^[[:alnum:]+/]{60,}$~		OK
#
#	# Put your own body patterns here.
# 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
#--
