NAME
procmailrc - procmail rcfileSYNOPSIS
$HOME/.procmailrcDESCRIPTION
For a quick start, see NOTES at the end of the procmail(1) man page. The rcfile can contain a mixture of environment variable assignments (some of which have special meanings to procmail), and recipes. In their most simple appearance, the recipes are simply one line regular expressions that are searched for in the header of the arriving mail. The first recipe that matches is used to determine where the mail has to go (usually a file). If processing falls off the end of the rcfile, procmail will deliver the mail to $DEFAULT. There are two kinds of recipes: delivering and non-delivering recipes. If a delivering recipe is found to match, procmail considers the mail (you guessed it) delivered and will cease processing the rcfile after having successfully executed the action line of the recipe. If a non-delivering recipe is found to match, processing of the rcfile will continue after the action line of this recipe has been executed. Delivering recipes are those that cause header and/or body of the mail to be: written into a file, absorbed by a program or forwarded to a mailaddress. Non-delivering recipes are: those that cause the output of a program or filter to be captured back by procmail or those that start a nesting block. You can tell procmail to treat a delivering recipe as if it were a non-delivering recipe by specifying the `c' flag on such a recipe. This will make procmail generate a carbon copy of the mail by delivering it to this recipe, yet continue processing the rcfile. By using any number of recipes you can presort your mail extremely straightforward into several mailfolders. Bear in mind though that the mail can arrive concurrently in these mailfolders (if several procmail programs happen to run at the same time, not unlikely if a lot of mail arrives). To make sure this does not result in a mess, proper use of lockfiles is highly recommended. The environment variable assignments and recipes can be freely intermixed in the rcfile. If any environment variable has a special meaning to procmail, it will be used appropriately the moment it is parsed (i.e., you can change the current directory whenever you want by specifying a new MAILDIR, switch lockfiles by specifying a new LOCKFILE, change the umask at any time, etc., the possibilities are endless :-). The assignments and substitutions of these environment variables are handled exactly like in sh(1) (that includes all possible quotes and escapes), with the added bonus that blanks around the '=' sign are ignored and that, if an environment variable appears without a trailing '=', it will be removed from the environment. Any program in backquotes started by procmail will have the entire mail at its stdin.Comments
A word beginning with # and all the following characters up to a NEWLINE are ignored. This does not apply to condition lines, which cannot be commented.Recipes
A line starting with ':' marks the beginning of a recipe. It has the following format::0 [ flags] [ : [locallockfile] ] <zero or more conditions (one per line)> <exactly one action line>
Conditions start with a leading `*', everything after that character is passed on to the internal egrep literally, except for leading and trailing whitespace. These regular expressions are completely compatible to the normal egrep(1) extended regular expressions. See also Extended regular expressions. Conditions are anded; if there are no conditions the result will be true by default. Flags can be any of the following:
- H
- Egrep the header (default).
- B
- Egrep the body.
- D
- Tell the internal egrep to distinguish between upper and
lower case (contrary to the default which is to ignore case).
- A
- This recipe will not be executed unless the conditions on
the last preceding recipe (on the current block-nesting level) without the
`A' or `a' flag matched as well. This allows you to chain actions that
depend on a common condition.
- a
- Has the same meaning as the `A' flag, with the additional
condition that the immediately preceding recipe must have been
successfully completed before this recipe is executed.
- E
- This recipe only executes if the immediately preceding
recipe was not executed. Execution of this recipe also disables any
immediately following recipes with the 'E' flag. This allows you to
specify `else if' actions.
- e
- This recipe only executes if the immediately preceding
recipe failed (i.e., the action line was attempted, but resulted in
an error).
- h
- Feed the header to the pipe, file or mail destination
(default).
- b
- Feed the body to the pipe, file or mail destination
(default).
- f
- Consider the pipe as a filter.
- c
- Generate a carbon copy of this mail. This only makes
sense on delivering recipes. The only non-delivering recipe this
flag has an effect on is on a nesting block, in order to generate a carbon
copy this will clone the running procmail process (lockfiles will
not be inherited), whereby the clone will proceed as usual and the parent
will jump across the block.
- w
- Wait for the filter or program to finish and check its
exitcode (normally ignored); if the filter is unsuccessful, then the text
will not have been filtered.
- W
- Has the same meaning as the `w' flag, but will suppress any
`Program failure' message.
- i
- Ignore any write errors on this recipe (i.e., usually due
to an early closed pipe).
- r
- Raw mode, do not try to ensure the mail ends with an empty line, write it out as is.
- !
- Invert the condition.
- $
- Evaluate the remainder of this condition according to
sh(1) substitution rules inside double quotes, skip leading
whitespace, then reparse it.
- ?
- Use the exitcode of the specified program.
- <
- Check if the total length of the mail is shorter than the
specified (in decimal) number of bytes.
- >
- Analogous to '<'.
- variablename ??
- Match the remainder of this condition against the value of
this environment variable (which cannot be a pseudo variable). A special
case is if variablename is equal to `B', `H', `HB' or `BH'; this merely
overrides the default header/body search area defined by the initial flags
on this recipe.
- \
- To quote any of the above at the start of the line.
Local lockfile
If you put a second (trailing) ':' on the first recipe line, then procmail will use a locallockfile (for this recipe only). You can optionally specify the locallockfile to use; if you don't however, procmail will use the destination filename (or the filename following the first '>>') and will append $LOCKEXT to it.Recipe action line
The action line can start with the following characters:- !
- Forwards to all the specified mail addresses.
- |
- Starts the specified program, possibly in $SHELL if any of
the characters $SHELLMETAS are spotted. You can optionally prepend this
pipe symbol with variable=, which will cause stdout of the program
to be captured in the environment variable (procmail will
not terminate processing the rcfile at this point). If you specify
just this pipe symbol, without any program, then procmail will pipe the
mail to stdout.
- {
- Followed by at least one space, tab or newline will mark the start of a nesting block. Everything up till the next closing brace will depend on the conditions specified for this recipe. Unlimited nesting is permitted. The closing brace exists merely to delimit the block, it will not cause procmail to terminate in any way. If the end of a block is reached processing will continue as usual after the block. On a nesting block, the flags `H' and `B' only affect the conditions leading up to the block, the flags `h' and `b' have no effect whatsoever.
Environment variable defaults
- LOGNAME, HOME and SHELL
- Your (the recipient's) defaults
- PATH
- $HOME/bin :/usr/local/bin :/usr/bin :/bin (Except during
the processing of an /etc/procmailrc file, when it will be set to
`/usr/local/bin :/usr/bin :/bin'.)
- SHELLMETAS
- & |<>~;?*[
- SHELLFLAGS
- -c
- ORGMAIL
- /var/mail/$LOGNAME
- MAILDIR
- $HOME
- DEFAULT
- $ORGMAIL
- MSGPREFIX
- msg.
- SENDMAIL
- /usr/sbin/sendmail
- SENDMAILFLAGS
- -oi
- HOST
- The current hostname
- COMSAT
- no
- PROCMAIL_VERSION
- 3.23pre
- LOCKEXT
- .lock
Environment
Before you get lost in the multitude of environment variables, keep in mind that all of them have reasonable defaults.- MAILDIR
- Current directory while procmail is executing (that means
that all paths are relative to $MAILDIR).
- DEFAULT
- Default mailbox file (if not told otherwise,
procmail will dump mail in this mailbox). Procmail will automatically use
$DEFAULT$LOCKEXT as lockfile prior to writing to this mailbox. You do not
need to set this variable, since it already points to the standard system
mailbox.
- LOGFILE
- This file will also contain any error or diagnostic
messages from procmail (normally none :-) or any other programs started by
procmail. If this file is not specified, any diagnostics or error messages
will be mailed back to the sender. See also LOGABSTRACT.
- VERBOSE
- You can turn on extended diagnostics by setting this
variable to `yes' or `on', to turn it off again set it to `no' or `off'.
- LOGABSTRACT
- Just before procmail exits it logs an abstract of the
delivered message in $LOGFILE showing the `From ' and `Subject:' fields of
the header, what folder it finally went to and how long (in bytes) the
message was. By setting this variable to `no', generation of this abstract
is suppressed. If you set it to `all', procmail will log an abstract for
every successful delivering recipe it processes.
- LOG
- Anything assigned to this variable will be appended to
$LOGFILE.
- ORGMAIL
- Usually the system mailbox (ORiGinal
MAILbox). If, for some obscure reason (like ` filesystem
full') the mail could not be delivered, then this mailbox will be the
last resort. If procmail fails to save the mail in here (deep, deep
trouble :-), then the mail will bounce back to the sender.
- LOCKFILE
- Global semaphore file. If this file already exists,
procmail will wait until it has gone before proceeding, and will create it
itself (cleaning it up when ready, of course). If more than one
lockfile are specified, then the previous one will be removed
before trying to create the new one. The use of a global lockfile is
discouraged, whenever possible use locallockfiles (on a per recipe basis)
instead.
- LOCKEXT
- Default extension that is appended to a destination file to
determine what local lockfile to use (only if turned on, on a
per-recipe basis).
- LOCKSLEEP
- Number of seconds procmail will sleep before retrying on a
lockfile (if it already existed); if not specified, it defaults to
8 seconds.
- LOCKTIMEOUT
- Number of seconds that have to have passed since a
lockfile was last modified/created before procmail decides that
this must be an erroneously leftover lockfile that can be removed by force
now. If zero, then no timeout will be used and procmail will wait forever
until the lockfile is removed; if not specified, it defaults to 1024
seconds. This variable is useful to prevent indefinite hangups of
sendmail/procmail. Procmail is immune to clock skew across
machines.
- TIMEOUT
- Number of seconds that have to have passed before procmail
decides that some child it started must be hanging. The offending program
will receive a TERMINATE signal from procmail, and processing of the
rcfile will continue. If zero, then no timeout will be used and procmail
will wait forever until the child has terminated; if not specified, it
defaults to 960 seconds.
- MSGPREFIX
- Filename prefix that is used when delivering to a directory
(not used when delivering to a maildir or an MH directory).
- HOST
- If this is not the hostname of the machine,
processing of the current rcfile will immediately cease. If other
rcfiles were specified on the command line, processing will continue with
the next one. If all rcfiles are exhausted, the program will terminate,
but will not generate an error (i.e., to the mailer it will seem that the
mail has been delivered).
- UMASK
- The name says it all (if it doesn't, then forget about this
one :-). Anything assigned to UMASK is taken as an octal number. If
not specified, the umask defaults to 077. If the umask permits o+x, all
the mailboxes procmail delivers to directly will receive an o+x mode
change. This can be used to check if new mail arrived.
- SHELLMETAS
- If any of the characters in SHELLMETAS appears in the line
specifying a filter or program, the line will be fed to $SHELL instead of
being executed directly.
- SHELLFLAGS
- Any invocation of $SHELL will be like:
- SENDMAIL
- If you're not using the forwarding facility don't
worry about this one. It specifies the program being called to forward any
mail.
- NORESRETRY
- Number of retries that are to be made if any `process
table full', ` file table full', `out of memory' or `
out of swap space' error should occur. If this number is negative,
then procmail will retry indefinitely; if not specified, it defaults to 4
times. The retries occur with a $SUSPEND second interval. The idea behind
this is that if, e.g., the swap space has been exhausted or
the process table is full, usually several other programs
will either detect this as well and abort or crash 8-), thereby freeing
valuable resources for procmail.
- SUSPEND
- Number of seconds that procmail will pause if it has to
wait for something that is currently unavailable (memory, fork, etc.); if
not specified, it will default to 16 seconds. See also: LOCKSLEEP.
- LINEBUF
- Length of the internal line buffers, cannot be set smaller
than 128. All lines read from the rcfile should not exceed $LINEBUF
characters before and after expansion. If not specified, it defaults to
2048. This limit, of course, does not apply to the mail itself,
which can have arbitrary line lengths, or could be a binary file for that
matter. See also PROCMAIL_OVERFLOW.
- DELIVERED
- If set to `yes' procmail will pretend (to the mail agent)
the mail has been delivered. If mail cannot be delivered after having met
this assignment (set to `yes'), the mail will be lost (i.e., it will not
bounce).
- TRAP
- When procmail terminates of its own accord and not because
it received a signal, it will execute the contents of this variable. A
copy of the mail can be read from stdin. Any output produced by this
command will be appended to $LOGFILE. Possible uses for TRAP are: removal
of temporary files, logging customised abstracts, etc. See also
EXITCODE and LOGABSTRACT.
- EXITCODE
- By default, procmail returns an exitcode of zero (success)
if it successfully delivered the message or if the HOST variable
was misset and there were no more rcfiles on the command line; otherwise
it returns failure. Before doing so, procmail examines the value of this
variable. If it is set to a positive numeric value, procmail will instead
use that value as its exitcode. If this variable is set but empty and
TRAP is set, procmail will set the exitcode to whatever the
TRAP program returns. If this variable is not set, procmail will
set it shortly before calling up the TRAP program.
- LASTFOLDER
- This variable is assigned to by procmail whenever it is
delivering to a folder or program. It always contains the name of the last
file (or program) procmail delivered to. If the last delivery was to
several directory folders together then $LASTFOLDER will contain the
hardlinked filenames as a space separated list.
- MATCH
- This variable is assigned to by procmail whenever it is
told to extract text from a matching regular expression. It will contain
all text matching the regular expression past the ` \/' token.
- SHIFT
- Assigning a positive value to this variable has the same
effect as the `shift' command in sh(1). This command is most useful
to extract extra arguments passed to procmail when acting as a generic
mailfilter.
- INCLUDERC
- Names an rcfile (relative to the current directory) which
will be included here as if it were part of the current rcfile. Nesting is
permitted and only limited by systems resources (memory and file
descriptors). As no checking is done on the permissions or ownership of
the rcfile, users of INCLUDERC should make sure that only trusted
users have write access to the included rcfile or the directory it is in.
Command line assignments to INCLUDERC have no effect.
- SWITCHRC
- Names an rcfile (relative to the current directory) to
which processing will be switched. If the named rcfile doesn't exist or is
not a normal file or /dev/null then an error will be logged and processing
will continue in the current rcfile. Otherwise, processing of the current
rcfile will be aborted and the named rcfile started. Unsetting
SWITCHRC aborts processing of the current rcfile as if it had ended
at the assignment. As with INCLUDERC, no checking is done on the
permissions or ownership of the rcfile and command line assignments have
no effect.
- PROCMAIL_VERSION
- The version number of the running procmail binary.
- PROCMAIL_OVERFLOW
- This variable will be set to a non-empty value if procmail
detects a buffer overflow. See the BUGS section below for other
details of operation when overflow occurs.
- COMSAT
-
Comsat(8)/biff(1) notification is on by
default, it can be turned off by setting this variable to `no'.
Alternatively the biff-service can be customised by setting it to either
`service@', `@hostname', or `service@hostname'. When not specified it
defaults to biff@localhost.
- DROPPRIVS
- If set to `yes' procmail will drop all privileges it might
have had (suid or sgid). This is only useful if you want to guarantee that
the bottom half of the /etc/procmailrc file is executed on behalf of the
recipient.
Extended regular expressions
The following tokens are known to both the procmail internal egrep and the standard egrep(1) (beware that some egrep implementations include other non-standard extensions; in particular, the repetition operator { is not supported by procmail's egrep):- ^
- Start of a line.
- $
- End of a line.
- .
- Any character except a newline.
- a*
- Any sequence of zero or more a's.
- a+
- Any sequence of one or more a's.
- a?
- Either zero or one a.
- [^-a-d]
- Any character which is not either a dash, a, b, c, d
or newline.
- de|abc
- Either the sequence `de' or `abc'.
- (abc)*
- Zero or more times the sequence `abc'.
- \.
- Matches a single dot; use \ to quote any of the magic characters to get rid of their special meaning. See also $\ variable substitution.
- ^ or $
- Match a newline (for multiline matches).
- ^^
- Anchor the expression at the very start of the search area,
or if encountered at the end of the expression, anchor it at the very end
of the search area.
- \< or \>
- Match the character before or after a word. They are merely
a shorthand for `[^a-zA-Z0-9_]', but can also match newlines. Since they
match actual characters, they are only suitable to delimit words, not to
delimit inter-word space.
- \/
- Splits the expression in two parts. Everything matching the
right part will be assigned to the MATCH environment variable.
EXAMPLES
Look in the procmailex(5) man page.CAVEATS
Continued lines in an action line that specifies a program always have to end in a backslash, even if the underlying shell would not need or want the backslash to indicate continuation. This is due to the two pass parsing process needed (first procmail, then the shell (or not, depending on SHELLMETAS)). Don't put comments on the regular expression condition lines in a recipe, these lines are fed to the internal egrep literally (except for continuation backslashes at the end of a line). Leading whitespace on continued regular expression condition lines is usually ignored (so that they can be indented), but not on continued condition lines that are evaluated according to the sh(1) substitution rules inside double quotes. Watch out for deadlocks when doing unhealthy things like forwarding mail to your own account. Deadlocks can be broken by proper use of LOCKTIMEOUT. Any default values that procmail has for some environment variables will always override the ones that were already defined. If you really want to override the defaults, you either have to put them in the rcfile or on the command line as arguments. The /etc/procmailrc file cannot change the PATH setting seen by user rcfiles as the value is reset when procmail finishes the /etc/procmailrc file. While future enhancements are expected in this area, recompiling procmail with the desired value is currently the only correct solution. Environment variables set inside the shell-interpreted-`|' action part of a recipe will not retain their value after the recipe has finished since they are set in a subshell of procmail. To make sure the value of an environment variable is retained you have to put the assignment to the variable before the leading `|' of a recipe, so that it can capture stdout of the program. If you specify only a `h' or a `b' flag on a delivering recipe, and the recipe matches, then, unless the `c' flag is present as well, the body respectively the header of the mail will be silently lost.SEE ALSO
procmail(1), procmailsc(5), procmailex(5), sh(1), csh(1), mail(1), mailx(1), uucp(1), aliases(5), sendmail(8), egrep(1), regexp(5), grep(1), biff(1), comsat(8), lockfile(1), formail(1)BUGS
The only substitutions of environment variables that can be handled by procmail itself are of the type $name, ${name}, ${name:-text}, ${name:+text}, ${name-text}, ${name+text}, $\name, $#, $n, $$, $?, $_, $- and $=; whereby $\name will be substituted by the all-magic-regular-expression-characters-disarmed equivalent of $name, $_ by the name of the current rcfile, $- by $LASTFOLDER and $= will contain the score of the last recipe. Furthermore, the result of $\name substitution will never be split on whitespace. When the -a or -m options are used, $# will expand to the number of arguments so specified and "$@" (the quotes are required) will expand to the specified arguments. However, "$@" will only be expanded when used in the argument list to a program, and then only one such occurrence will be expanded. Unquoted variable expansions performed by procmail are always split on space, tab, and newline characters; the IFS variable is not used internally. Procmail does not support the expansion of `~'. A line buffer of length $LINEBUF is used when processing the rcfile, any expansions that don't fit within this limit will be truncated and PROCMAIL_OVERFLOW will be set. If the overflowing line is a condition or an action line, then it will be considered failed and procmail will continue processing. If it is a variable assignment or recipe start line then procmail will abort the entire rcfile. If the global lockfile has a relative path, and the current directory is not the same as when the global lockfile was created, then the global lockfile will not be removed if procmail exits at that point (remedy: use absolute paths to specify global lockfiles). If an rcfile has a relative path and when the rcfile is first opened MAILDIR contains a relative path, and if at one point procmail is instructed to clone itself and the current directory has changed since the rcfile was opened, then procmail will not be able to clone itself (remedy: use an absolute path to reference the rcfile or make sure MAILDIR contains an absolute path as the rcfile is opened). A locallockfile on the recipe that marks the start of a non-forking nested block does not work as expected. When capturing stdout from a recipe into an environment variable, exactly one trailing newline will be stripped. Some non-optimal and non-obvious regexps set MATCH to an incorrect value. The regexp can be made to work by removing one or more unneeded '*', '+', or '?' operator on the left-hand side of the \/ token.MISCELLANEOUS
If the regular expression contains ` ^TO_' it will be substituted by ` (^((Original-)?(Resent-)?(To |Cc |Bcc) |(X-Envelope |Apparently(-Resent)?)-To) :(.*[^-a-zA-Z0-9_.])?)', which should catch all destination specifications containing a specific address. If the regular expression contains ` ^TO' it will be substituted by ` (^((Original-)?(Resent-)?(To |Cc |Bcc) |(X-Envelope |Apparently(-Resent)?)-To) :(.*[^a-zA-Z])?)', which should catch all destination specifications containing a specific word. If the regular expression contains ` ^FROM_DAEMON' it will be substituted by ` (^(Mailing-List : |Precedence :.*(junk |bulk |list) |To : Multiple recipients of |(((Resent-)?(From |Sender) |X-Envelope-From) : |>?From )([^>]*[^(.%@a-z0-9])?(Post(ma?(st(e?r)? |n) |office) |(send)?Mail(er)? |daemon |m(mdf |ajordomo) |n?uucp |LIST(SERV |proc) |NETSERV |o(wner |ps) |r(e(quest |sponse) |oot) |b(ounce |bs\.smtp) |echo |mirror |s(erv(ices? |er) |mtp(error)? |ystem) |A(dmin(istrator)? |MMGR |utoanswer))(([^).! :a-z0-9][-_a-z0-9]*)?[%@>\t ][^<)]*(\(.*\).*)?)?$([^>] |$)))', which should catch mails coming from most daemons (how's that for a regular expression :-). If the regular expression contains ` ^FROM_MAILER' it will be substituted by ` (^(((Resent-)?(From |Sender) |X-Envelope-From) : |>?From )([^>]*[^(.%@a-z0-9])?(Post(ma(st(er)? |n) |office) |(send)?Mail(er)? |daemon |mmdf |n?uucp |ops |r(esponse |oot) |(bbs\.)?smtp(error)? |s(erv(ices? |er) |ystem) |A(dmin(istrator)? |MMGR))(([^).! :a-z0-9][-_a-z0-9]*)?[%@>\t ][^<)]*(\(.*\).*)?)?$([^>] |$))' (a stripped down version of ` ^FROM_DAEMON'), which should catch mails coming from most mailer-daemons. When assigning boolean values to variables like VERBOSE, DELIVERED or COMSAT, procmail accepts as true every string starting with: a non-zero value, `on', `y', `t' or `e'. False is every string starting with: a zero value, `off', `n', `f' or `d'. If the action line of a recipe specifies a program, a sole backslash-newline pair in it on an otherwise empty line will be converted into a newline. The regular expression engine built into procmail does not support named character classes.NOTES
Since unquoted leading whitespace is generally ignored in the rcfile you can indent everything to taste. The leading `|' on the action line to specify a program or filter is stripped before checking for $SHELLMETAS. Files included with the INCLUDERC directive containing only environment variable assignments can be shared with sh. The current behavior of assignments on the command line to INCLUDERC and SWITCHRC is not guaranteed, has been changed once already, and may be changed again or removed in future releases. For really complicated processing you can even consider calling procmail recursively. In the old days, the `:0' that marks the beginning of a recipe, had to be changed to `:n', whereby `n' denotes the number of conditions that follow.AUTHORS
Stephen R. van den BergPhilip A. Guenther
2001/08/04 | BuGless |