This is an extract from the ListProcessor User Manual with instructions on how to access a list archive. In the following, archive would be imod, serialem, or peet-list; there is no password; and there are no subarchives so -all is unneeded. Archives for imod and serialem were started on May 5, 2008, and for peet-list on April 27, 2012. Send your commands to email@example.com.
The Corporation for Research and Educational Networking
V. Archive commands (GET, INDEX, SEARCH)
Many lists maintain archives. Archives may contain copies of all old mail that has passed out over the list or may contain special files that the list owner didn't want to send out via e-mail but did want to make available to all subscribers. Archives may be public or private. Private archives require the /password parameter. In the following, archive may be replaced by:
list-name At most sites, the list-name and archive are the same. If your site does not recognize your list-name as a valid archive, check with your list owner.
archive-name An alternate name given to the archive by the list owner.
path-to-archive - the full path to the archive as returned by INDEX.
INDex archive [/password] [-all]
List files in the selected archive, or the master archive if no archive was specified. The path to the archive is returned with the index. If you send an INDEX command without the name of the list or archive, ListProc will return an index of all public archives available on the host system. Archives may contain multiple subarchives; using a directory tree as an example, an archive may consist of a root archive with multiple subdirectories or subarchives within. The INDEX command will return only the one level of archive or directory requested; in order to obtain the entire archive structure including all subarchives the -all arguement must be added onto the INDEX command. In the event the archive is private you will have to use your list password or a password given to you by the list owner in order to obtain an index. The password must be preceded by a slash "/" when including it in an INDEX command.
SEArch [archive] [/password] [-all] [pattern]
If you are looking for a specific file but do not know what archive it is located in, you can search all files of the host system or of a specific archive (and all of its subarchives if -all is specified) for lines that match pattern. Once again, if the archive is password protected you must specify the password with a slash "/" before it.
[Note: Pattern may be enclosed in single or double quotes and can be a regular expression with support for these additional operators:
'^' provides negation
'|' and '&' provide logical OR and AND
'<' and '>' are used to group parts of regular expressions
'.' matches any character including new line
See the discussion on regular expressions below.
GET archive file [/password]
Get file from the specified archive. Once you have located the file you want to get using either an INDEX or a SEARCH command you can get that file with a get command. The requested file will be e-mailed to you. If the file is very large it may be split into multiple smaller parts in order to be e-mailed to you. Binary files cannot be sent via e-mail so if the file is a binary file it will be encoded to text using uuencode and you will have to obtain a copy of uudecode in order to convert the file back into it's original binary type. In the event the file is located in a private archive you will have to use your list password or a password given to you by the list owner in order to obtain the file. The password must be preceded by a slash "/" when including it in a GET command.
VIII. Regular Expressions
Many ListProc command lines take regular expressions as arguments. A regular expression is a group of symbols which describe a unique string of characters. An example of a simple regular expression is the word "donkey". In a group of words, the regular expression "donkey" matches only other instances of the word "donkey" and nothing else. So if we had a text file and did a search for "donkey" every time that word appeared in the text it would show up in our search. This definition can be expanded if we define the period "." as a wild card replacement for a single character. Then the regular expression ".onkey" would include "honkey" or "tonkey" or "bonkey" as well as "donkey". We can continue to expand on the definition by adding the asterisk to the period " .* " as a substitute for any number of characters. Then the regular expression "don.* " will not only include "donkey" but will include all strings of characters beginning with "don" including "don" itself. A search of a text file for "don.* " will turn up dongle, donkey, donner, dondoodit, dondiddle, etc. Regular expression matching, therefore, puts together a whole set of rules that allow you to test whether a string fits into a specific syntactic shape. You can also search a string for a substring that fits a pattern, and just as importantly, you can replace one string with another. The command line of a ListProc command is more like a regular expression as used in a database search.
Regular expressions have a syntax in which a few characters are special constructs and the rest are "ordinary". An ordinary character is a simple regular expression which matches that character and nothing else. The special characters are `$', `^', `.', `*', `+', `?', `[', `]' and `\'. Any other character appearing in a regular expression is ordinary, unless a `\' precedes it.
For example, `f' is not a special character, so it is ordinary, and therefore `f' is a regular expression that matches the string `f' and no other string. (It does not match the string `ff'.) Likewise, `o' is a regular expression that matches only `o'.
Any two regular expressions A and B can be concatenated. The result is a regular expression which matches a string if A matches some amount of the beginning of that string and B matches the rest of the string.
As a simple example, we can concatenate the regular expressions `f' and `o' to get the regular expression `fo', which matches only the string `fo'. Still trivial.
The characters and character sequences which have special meaning within regular expressions are referred to as "operators". Some of the operators recognized by ListProcessor are listed below.
Any character not mentioned here is not special; it stands for exactly itself for the purposes of searching and matching.
is a special character that matches anything except a newline. Using concatenation, we can make regular expressions like `a.b' which matches any three-character string which begins with `a' and ends with `b'.
is not a construct by itself; it is a suffix, which means the preceding regular expression is to be repeated as many times as possible. In `fo*', the `*' applies to the `o', so `fo*' matches `f' followed by any number of `o''s. The case of zero `o''s is allowed: `fo*' does match `f'.
`*' always applies to the *smallest* possible preceding expression. Thus, `fo*' has a repeating `o', not a repeating `fo'. The matcher processes a `*' construct by matching, immediately, as many repetitions as can be found. Then it continues with the rest of the pattern. If that fails, backtracking occurs, discarding some of the matches of the `*''d construct in case that makes it possible to match the rest of the pattern. For example, matching `c[ad]*ar' against the string `caddaar', the `[ad]*' first matches `addaa', but this does not allow the next `a' in the pattern to match. So the last of the matches of `[ad]' is undone and the following `a' is tried again. Now it succeeds.
`+' is like `*' except that at least one match for the preceding pattern is required for `+'. Thus, `c[ad]+r' does not match `cr' but does match anything else that `c[ad]*r' would match.
`?' is like `*' except that it allows either zero or one match for the preceding pattern. Thus, `c[ad]?r' matches `cr' or `car' or `cdr', and nothing else.
`[ ... ]'
`[' begins a "character set", which is terminated by a `]'. In the simplest case, the characters between the two form the set. Thus, `[ad]' matches either `a' or `d', and `[ad]*' matches any string of `a''s and `d''s (including the empty string), from which it follows that `c[ad]*r' matches `car', etc.
Character ranges can also be included in a character set, by writing two characters with a `-' between them. Thus, `[a-z]' matches any lower-case letter. Ranges may be intermixed freely with individual characters, as in `[a-z$%.]', which matches any lower case letter or `$', `%' or period.
Note that the usual special characters are not special any more inside a character set. A completely different set of special characters exists inside character sets: `]', `-' and `^'. To include a `]' in a character set, you must make it the first character. For example, `a]' matches `]' or `a'. To include
a `-', you must use it in a context where it cannot possibly indicate a range: that is, as the first character, or immediately after a range.
`[^ ... ]'
`[^' begins a "complement character set", which matches any character except the ones specified. Thus, `[^a-z0-9A-Z]' matches all characters except letters and digits. Note that the ^ has to be within brackets. Outside of brackets it has a different meaning as mentioned below. `^' is not special in a character set unless it is the first character. The character following the `^' is treated as if it were first (it may be a `-' or a `]').
is a special character that matches the empty string -- but only if at the beginning of a line in the text being matched. Otherwise it fails to match anything. Thus, `^foo' matches a `foo' which occurs at the beginning of a line.
is similar to `^' but matches only at the end of a line. Thus, `xx*$' matches a string of one or more `x''s at the end of a line.
has two functions: it quotes the above special characters (including `\'), and it introduces additional special constructs. If you wanted to search for the dollar sign within a text you would have to use \$ in place of just $ since the dollar sign has a special meaning. Because `\' quotes special characters, `\$' is a regular expression which matches only `$', and `\[' is a regular expression which matches only `[', and so on.
For the most part, `\' followed by any character matches only that character. However, there are several exceptions: characters which, when preceded by `\', are special constructs. Such characters are always ordinary when encountered on their own.
No new special characters will ever be defined. All extensions to the regular expression syntax are made by defining new two-character constructs that begin with `\'.
specifies an alternative. Two regular expressions A and B with `\|' in between form an expression that matches anything that either A or B will match. Thus, `foo\|bar' matches either `foo' or `bar' but no other string. `\|' applies to the largest possible surrounding expressions. Only a surrounding `\( ... \)' grouping can limit the grouping power of `\|'. Full backtracking capability exists when multiple `\|''s are used.
`\( ... \)'
is a grouping construct that serves three purposes:
1. To enclose a set of `\|' alternatives for other operations. Thus, `\(foo\|bar\)x' matches either `foox' or `barx'.
2. To enclose a complicated expression for the postfix `*' to operate on. Thus, `ba\(na\)*' matches `bananana', etc., with any (zero or more) number of `na''s.
3. To mark a matched substring for future reference. This last application is not a consequence of the idea of a parenthetical grouping; it is a separate feature which happens to be assigned as a second meaning to the same `\( ... \)' construct because there is no conflict in practice between the two meanings. Here is an explanation of this feature:
After the end of a `\( ... \)' construct, the matcher remembers the beginning and end of the text matched by that construct. Then, later on in the regular expression, you can use `\' followed by DIGIT to mean "match the same text matched the DIGIT'th time by the `\( ... \)' construct." The `\( ... \)' constructs are numbered in order of commencement in the regexp.
The strings matching the first nine `\( ... \)' constructs appearing in a regular expression are assigned numbers 1 through 9 in order of their beginnings. `\1' through `\9' may be used to refer to the text matched by the corresponding `\( ... \)' construct.
For example, `\(.*\)\1' matches any string that is composed of two identical halves. The `\(.*\)' matches the first half, which may be anything, but the `\1' that follows must match the same exact text.
matches the empty string, but only if it is at the beginning or end of a word. Thus, `\bfoo\b' matches any occurrence of `foo' as a separate word. `\bball\(s\|\)\b' matches `ball' or `balls' as a separate word.
matches the empty string, provided it is *not* at the beginning or end of a word.
matches the empty string, but only if it is at the beginning of a word.
matches the empty string, but only if it is at the end of a word.
matches any word-constituent character.
matches any character that is not a word-constituent. What the `\( ... \)' groupings matched.
Here are examples of commands that use regular expressions:
lists global 'health|mental'~death
The above will compile a list of lists that contain either the word 'health' or 'mental' in either their list name or description comment but will exclude lists with the word 'death'. The way you should read 'health|mental'~death out loud is; "health or mental but not death".
lists global move$&dan$
will search for all lists containing BOTH the characters 'move' AND 'dan' so that move$ will return both movement and movies and dan$ will return both dancing and danger. But in order for you to receive a reply, the list will have to contain BOTH words. So a list about Dangerous Movies will show up in your search as well as a list about Movement and Dancing.
search mylist-l bart@^ar..+beta.org
This example will search for messages in the mylist-l archive for all messages containing references to a user named bart whether he posts from ar1.beta.org or from ar2.beta.org or art.beta.org. In this manner you can turn up all his messages no matter which machine he posted from.