# 
# PCRE_TABLE(5)                                       PCRE_TABLE(5)
# 
# NAME
#        pcre_table - 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 dbm
#        or  db  format. Alternatively, lookup tables can be speci-
#        fied in Perl Compatible Regular Expression form.
# 
#        To find out what types of lookup tables your Postfix  sys-
#        tem supports use the postconf -m command.
# 
#        The general form of a PCRE table is:
# 
#        blanks and comments
#               Blank  lines  are  ignored,  as are lines beginning
#               with `#'.
# 
#        leading whitespace
#               Lines that begin with whitespace continue the  pre-
#               vious line.
# 
#        pattern result
#               When  pattern matches a search string, use the cor-
#               responding result. A line that  starts  with  white
#               space continues the preceding line.
# 
#        Each  pattern  is  a  perl-like  regular  expression.  The
#        expression delimiter can be any character, except  whites-
#        pace  or  characters that have special meaning (tradition-
#        ally the forward slash is used).  The  regular  expression
#        can contain whitespace.
# 
#        By default, matching is case-insensitive, although follow-
#        ing 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 documenta-
#        tion 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 user@domain mail addresses are
#        not broken up  into  their  user  and  domain  constituent
#        parts, nor is user+foo broken up into user and foo.
# 
#        Patterns  are  applied  in  the  order as specified in the
#        table, until a pattern is found that  matches  the  search
#        string.
# 
#                                                                 1
# 
# PCRE_TABLE(5)                                       PCRE_TABLE(5)
# 
#        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 $(n) if they aren't followed by whites-
#        pace.
# 
# EXAMPLES
#        # Protect your outgoing majordomo exploders
#        /^(?!owner-)(.*)-outgoing@(my.domain)$/    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
# 
#                                                                 2
# 
