From: Nigel Metheringham Date: Thu, 17 Jan 2008 13:14:07 +0000 (+0000) Subject: Removed old documentation source files to prevent confusion. Fixes: #658 X-Git-Tag: DEVEL_PDKIM_START~82 X-Git-Url: https://git.exim.org/users/jgh/exim.git/commitdiff_plain/0caec8e792b969ca442413e75c8966f074bc5fd4 Removed old documentation source files to prevent confusion. Fixes: #658 --- diff --git a/doc/doc-src/ABOUT b/doc/doc-src/ABOUT index 990790101..35b77f247 100644 --- a/doc/doc-src/ABOUT +++ b/doc/doc-src/ABOUT @@ -1,4 +1,4 @@ -$Cambridge: exim/doc/doc-src/ABOUT,v 1.2 2005/06/16 10:32:31 ph10 Exp $ +$Cambridge: exim/doc/doc-src/ABOUT,v 1.3 2008/01/17 13:14:07 nm4 Exp $ CVS directory exim/exim-doc/doc-src ----------------------------------- @@ -11,4 +11,7 @@ Subsequent documentation releases operate using DocBook input, so these files are now historical relics. The FAQ source is still (June 2005) current, but may be superseded in due course. +The filter and spec source files have now been removed from here to +prevent further confusion. + End diff --git a/doc/doc-src/filter.src b/doc/doc-src/filter.src deleted file mode 100644 index 8688721af..000000000 --- a/doc/doc-src/filter.src +++ /dev/null @@ -1,1735 +0,0 @@ -. $Cambridge: exim/doc/doc-src/filter.src,v 1.2 2005/01/11 15:17:51 ph10 Exp $ -. -.if !set style -.library "a4ps" -.linelength ~~sys.linelength + 0.2in -.emphasis ~~sys.linelength + 0.1in -.pagedepth ~~sys.pagedepth - 0.2in -.bindfont 53 "atl/Times-Roman" 7 -.set ssspaceb 1.50 -.fi - -.include "markup.sg" - -.set sgcal true -.set html false -.set texinfo false - - -.if ~~sys.fancy -.flag $sm{ "$push$g0$f53" -. -.else -.pagedepth ~~sys.pagedepth - 1ld -.linelength 75em -.emphasis 77em -.footdepth 0 -.disable formfeed -.backspace none -.set chapspaceb 24 -.set sspacea 24 -.flag $sm{ "$push" -.fi - -.macro tabs 6 -.if ~~sys.fancy -.tabset ~~1em -.else -.set temp (~~1 * 5)/4 -.tabset ~~temp em -.fi -.endm - -.macro startitems -.newline -.push -.indent 3em -.endm - -.macro enditems -.newline -.pop -.endm - -.macro item "item" -.newpar -.if ~~sys.leftonpage < 5ld -.newpage -.fi -.tempindent 0 -\~~1\ -.blank -.endm - -.macro index -.endm - -.set contents false -.set displayindent 2em - - -. ====================================================== - - -.if ~~sys.fancy -.footdepth 2ld -.foot -$c[~~sys.pagenumber]$e -.endfoot -.fi - - -.set chapter -1 -.chapter Exim's interfaces to mail filtering -.space -2ld -This document describes the user interfaces to Exim's in-built mail filtering -facilities, and is copyright (c) University of Cambridge 2005. It corresponds -to Exim version 4.50. -.rule - -. --------------------------------------------------------------------------- -. Some clever jiggery-pokery here. The contents list is known to be less than -. one page long, so we arrange for it to get onto the rest of the first page. -. Because we aren't doing any indexing, the z-rawindex file will contain only -. the TOC entries. The Makefile arranges for it to be empty at the start, then -. runs SGCAL twice so on the second pass it gets inserted automatically. - -.if ~~sgcal -.space 1ld -. $chead{Contents} -. space 1ld -.tabset 2em 2em -.push -.linedepth ~~sys.linedepth - 1 -.include "z-rawindex" -.newline -.pop -.newpage -.set contents true -.fi -. --------------------------------------------------------------------------- - - -.set chapter 0 -.chapter Forwarding and filtering in Exim - - -.section Introduction -Most Unix mail transfer agents (programs that deliver mail) permit individual -users to specify automatic forwarding of their mail, usually by placing a list -of forwarding addresses in a file called \(.forward)\ in their home directories. -Exim extends this facility by allowing the forwarding instructions to be a set -of rules rather than just a list of addresses, in effect providing `\(.forward)\ -with conditions'. Operating the set of rules is called $it{filtering}, and the -file that contains them is called a $it{filter file}. - -Exim supports two different kinds of filter file. An \*Exim filter*\ contains -instructions in a format that is unique to Exim. A \*Sieve filter*\ contains -instructions in the Sieve format that is defined by RFC 3028. As this is a -standard format, Sieve filter files may already be familiar to some users. -Sieve files should also be portable between different environments. However, -the Exim filtering facility contains more features (such as variable -expansion), and better integration with the host environment (such as the use -of external processes and pipes). - -The choice of which kind of filter to use can be left to the end-user, provided -that the system administrator has configured Exim appropriately for both kinds -of filter. However, if interoperability is important, Sieve is the only -choice. - -The ability to use filtering or traditional forwarding has to be enabled by the -system administrator, and some of the individual facilities can be separately -enabled or disabled. A local document should be provided to describe exactly -what has been enabled. In the absence of this, consult your system -administrator. - -This document describes how to use a filter file and the format of its -contents. It is intended for use by end-users. Both Sieve filters and Exim -filters are covered. However, for Sieve filters, only issues that relate to the -Exim implementation are discussed, since Sieve itself is described elsewhere. - -The contents of traditional \(.forward)\ files are not described here. They -normally contain just a list of addresses, file names, or pipe commands, -separated by commas or newlines, but other types of item are also available. -The full details can be found in the chapter on the \%redirect%\ router in the -Exim specification, which also describes how the system administrator can set -up and control the use of filtering. - - -.em -.section Filter operation -It is important to realize that, in Exim, no deliveries are actually made while -a filter or traditional \(.forward)\ file is being processed. Running a filter -or processing a traditional \(.forward)\ file sets up future delivery -operations, but does not carry them out. - -The result of filter or \(.forward)\ file processing is a list of destinations -to which a message should be delivered. The deliveries themselves take place -later, along with all other deliveries for the message. This means that it is -not possible to test for successful deliveries while filtering. It also means -that any duplicate addresses that are generated are dropped, because Exim never -delivers the same message to the same address more than once. -.nem - - -.section Testing a new filter file -.rset SECTtesting "~~chapter.~~section" -Filter files, especially the more complicated ones, should always be tested, as -it is easy to make mistakes. Exim provides a facility for preliminary testing -of a filter file before installing it. This tests the syntax of the file and -its basic operation, and can also be used with traditional \(.forward)\ files. - -Because a filter can do tests on the content of messages, a test message is -required. Suppose you have a new filter file called \(myfilter)\ and a test -message called \(test-message)\. Assuming that Exim is installed with the -conventional path name \(/usr/sbin/sendmail)\ (some operating systems use -\(/usr/lib/sendmail)\), the following command can be used: -.display asis -/usr/sbin/sendmail -bf myfilter > to <> -e.g. add 2 to n3 -.endd -There are 10 user variables of this type, with names \"n0"\ -- \"n9"\. Their -values can be obtained by the normal expansion syntax (for example \$n3$\) in -other commands. At the start of filtering, these variables all contain zero. -Both arguments of the \"add"\ command are expanded before use, making it -possible to add variables to each other. Subtraction can be obtained by adding -negative numbers. - - -.section The deliver command -.rset SECTdeliver "~~chapter.~~section" -.display - deliver <> -e.g. deliver "Dr Livingstone " -.endd -This command provides a forwarding operation. -.em -The delivery that it sets up is significant unless the command is preceded by -\"unseen"\ (see section ~~SECTsigdel). -.nem -The message is sent on to the given address, exactly as happens if the address -had appeared in a traditional \(.forward)\ file. If you want to deliver the -message to a number of different addresses, you can use more than one -\"deliver"\ command (each one may have only one address). However, duplicate -addresses are discarded. - -To deliver a copy of the message to your normal mailbox, your login name can be -given as the address. Once an address has been processed by the filtering -mechanism, an identical generated address will not be so processed again, so -doing this does not cause a loop. - -However, if you have a mail alias, you should $it{not} refer to it here. For -example, if the mail address \"L.Gulliver"\ is aliased to \"lg303"\ then all -references in Gulliver's \(.forward)\ file should be to \"lg303"\. A reference -to the alias will not work for messages that are addressed to that alias, -since, like \(.forward)\ file processing, aliasing is performed only once on an -address, in order to avoid looping. - -Following the new address, an optional second address, preceded by -\"errors@_to"\ may appear. This changes the address to which delivery errors on -the forwarded message will be sent. Instead of going to the message's original -sender, they go to this new address. For ordinary users, the only value that is -permitted for this address is the user whose filter file is being processed. -For example, the user \"lg303"\ whose mailbox is in the domain -\lilliput.example\ could have a filter file that contains -.display asis - deliver jon@elsewhere.example errors_to lg303@lilliput.example -.endd -Clearly, using this feature makes sense only in situations where not all -messages are being forwarded. In particular, bounce messages must not be -forwarded in this way, as this is likely to create a mail loop if something -goes wrong. - - -.section The save command -.rset SECTsave "~~chapter.~~section" -.display - save <> -e.g. save @$home/mail/bookfolder -.endd -.em -This command specifies that a copy of the message is to be appended to the -given file (that is, the file is to be used as a mail folder). The delivery -that \"save"\ sets up is significant unless the command is preceded by -\"unseen"\ (see section ~~SECTsigdel). -.nem -More than one \"save"\ command may be obeyed; each one causes a copy of the -message to be written to its argument file, provided they are different -(duplicate \"save"\ commands are ignored). - -If the file name does not start with a / character, the contents of the -\$home$\ variable are prepended, unless it is empty. In conventional -configurations, this variable is normally set in a user filter to the user's -home directory, but the system administrator may set it to some other path. In -some configurations, \$home$\ may be unset, in which case a non-absolute path -name may be generated. Such configurations convert this to an absolute path -when the delivery takes place. In a system filter, \$home$\ is never set. - -The user must of course have permission to write to the file, and the writing -of the file takes place in a process that is running as the user, under the -user's primary group. Any secondary groups to which the user may belong are not -normally taken into account, though the system administrator can configure Exim -to set them up. In addition, the ability to use this command at all is -controlled by the system administrator -- it may be forbidden on some systems. - -An optional mode value may be given after the file name. The value for the mode -is interpreted as an octal number, even if it does not begin with a zero. For -example: -.display - save /some/folder 640 -.endd -This makes it possible for users to override the system-wide mode setting for -file deliveries, which is normally 600. If an existing file does not have the -correct mode, it is changed. - -An alternative form of delivery may be enabled on your system, in which each -message is delivered into a new file in a given directory. If this is the case, -this functionality can be requested by giving the directory name terminated by -a slash after the \"save"\ command, for example -.display - save separated/messages/ -.endd -There are several different formats for such deliveries; check with your system -administrator or local documentation to find out which (if any) are available -on your system. If this functionality is not enabled, the use of a path name -ending in a slash causes an error. - - -.section The pipe command -.rset SECTpipe "~~chapter.~~section" -.display - pipe <> -e.g. pipe "@$home/bin/countmail @$sender@_address" -.endd -.em -This command specifies that the message is to be delivered to the specified -command using a pipe. The delivery that it sets up is significant unless the -command is preceded by \"unseen"\ (see section ~~SECTsigdel). -.nem -Remember, however, that no deliveries are done while the filter is being -processed. All deliveries happen later on. Therefore, the result of running the -pipe is not available to the filter. - -When the deliveries are done, a separate process is run, and a copy of the -message is passed on its standard input. The process runs as the user, under -the user's primary group. Any secondary groups to which the user may belong are -not normally taken into account, though the system administrator can configure -Exim to set them up. More than one \"pipe"\ command may appear; each one causes -a copy of the message to be written to its argument pipe, provided they are -different (duplicate \"pipe"\ commands are ignored). - -When the time comes to transport the message, -the command supplied to \"pipe"\ is split up by Exim into a command name and a -number of arguments. These are delimited by white space except for arguments -enclosed in double quotes, in which case backslash is interpreted as an escape, -or in single quotes, in which case no escaping is recognized. Note that as the -whole command is normally supplied in double quotes, a second level of quoting -is required for internal double quotes. For example: -.display asis - pipe "$home/myscript \"size is $message_size\"" -.endd -String expansion is performed on the separate components after the line has -been split up, and the command is then run directly by Exim; it is not run -under a shell. Therefore, substitution cannot change the number of arguments, -nor can quotes, backslashes or other shell metacharacters in variables cause -confusion. - -Documentation for some programs that are normally run via this kind of pipe -often suggest that the command should start with -.display asis -IFS=" " -.endd -This is a shell command, and should $it{not} be present in Exim filter files, -since it does not normally run the command under a shell. - -However, there is an option that the administrator can set to cause a shell to -be used. In this case, the entire command is expanded as a single string and -passed to the shell for interpretation. It is recommended that this be avoided -if at all possible, since it can lead to problems when inserted variables -contain shell metacharacters. - -The default \\PATH\\ set up for the command is determined by the system -administrator, usually containing at least \/usr/bin\ so that common commands -are available without having to specify an absolute file name. However, it is -possible for the system administrator to restrict the pipe facility so that the -command name must not contain any / characters, and must be found in one of the -directories in the configured \\PATH\\. It is also possible for the system -administrator to lock out the use of the \"pipe"\ command altogether. - -When the command is run, a number of environment variables are set up. The -complete list for pipe deliveries may be found in the Exim reference manual. -Those that may be useful for pipe deliveries from user filter files are: -.display -.tabs 20 -DOMAIN $t $rm{the domain of the address} -HOME $t $rm{your home directory} -LOCAL@_PART $t $rm{see below} -LOCAL@_PART@_PREFIX $t $rm{see below} -LOCAL@_PART@_SUFFIX $t $rm{see below} -LOGNAME $t $rm{your login name} -MESSAGE@_ID $t $rm{the message's unique id} -PATH $t $rm{the command search path} -RECIPIENT $t $rm{the complete recipient address} -SENDER $t $rm{the sender of the message} -SHELL $t $bf{/bin/sh} -USER $t $rm{see below} -.endd -\\LOCAL@_PART\\, \\LOGNAME\\, and \\USER\\ are all set to the same value, -namely, your login id. \\LOCAL@_PART@_PREFIX\\ and \\LOCAL@_PART@_SUFFIX\\ may -be set if Exim is configured to recognize prefixes or suffixes in the local -parts of addresses. For example, a message addressed to -\*pat-suf2@@domain.example*\ may cause user \*pat*\'s filter file to be run. If -this sets up a pipe delivery, \\LOCAL@_PART@_SUFFIX\\ is \"-suf2"\ when the -pipe command runs. The system administrator has to configure Exim specially for -this feature to be available. - -If you run a command that is a shell script, be very careful in your use of -data from the incoming message in the commands in your script. RFC 2822 is very -generous in the characters that are legally permitted to appear in mail -addresses, and in particular, an address may begin with a vertical bar or a -slash. For this reason you should always use quotes round any arguments that -involve data from the message, like this: -.display asis -/some/command '$SENDER' -.endd -so that inserted shell meta-characters do not cause unwanted effects. - -Remember that, as was explained earlier, the pipe command is not run at the -time the filter file is interpreted. The filter just defines what deliveries -are required for one particular addressee of a message. The deliveries -themselves happen later, once Exim has decided everything that needs to be done -for the message. - -A consequence of this is that you cannot inspect the return code from the pipe -command from within the filter. Nevertheless, the code returned by the command -is important, because Exim uses it to decide whether the delivery has succeeded -or failed. - -The command should return a zero completion code if all has gone well. Most -non-zero codes are treated by Exim as indicating a failure of the pipe. This is -treated as a delivery failure, causing the message to be returned to its -sender. However, there are some completion codes that are treated as temporary -errors. The message remains on Exim's spool disk, and the delivery is tried -again later, though it will ultimately time out if the delivery failures go on -too long. The completion codes to which this applies can be specified by the -system administrator; the default values are 73 and 75. - -The pipe command should not normally write anything to its standard output or -standard error file descriptors. If it does, whatever is written is normally -returned to the sender of the message as a delivery error, though this action -can be varied by the system administrator. - - -.section Mail commands -.rset SECTmail "~~chapter.~~section" -There are two commands that cause the creation of a new mail message, neither -of which count as a significant delivery unless the command is preceded by the -word \"seen"\ (see section ~~SECTsigdel). This is a powerful facility, but it -should be used with care, because of the danger of creating infinite sequences -of messages. The system administrator can forbid the use of these commands -altogether. - -To help prevent runaway message sequences, these commands have no effect when -the incoming message is a bounce (delivery error) message, and messages sent by -this means are treated as if they were reporting delivery errors. Thus, they -should never themselves cause a bounce message to be returned. The basic -mail-sending command is -.display - mail [to <>] - [cc <>] - [bcc <>] - [from <
>] - [reply@_to <
>] - [subject <>] - [extra@_headers <>] - [text <>] - [[expand] file <>] - [return message] - [log <>] - [once <>] - [once@_repeat <