glimpseindex.1

harvest是一个下载html网页得机器人

The default value is 80%.
(If there are less than 256 files, then the stop-list is not maintained.)
The medium index (-b) counts all occurrences of all words, and a word
is added to the stop-list if it appears at least k times per MByte.
The default value is 500.
A query that includes a stop list word is of course less efficient.
(See also LIMITATIONS below.)
.TP
.B \-t 
(A new option in version 3.5.)
The order in which files are indexed is determined by scanning
the directories, which is mostly arbitrary.
With the \-t option, combined with either \-o and \-b, 
the indexed files are stored in reversed order of 
modification age (younger files first).
Results of queries are then automatically returned in this order.
Furthermore, glimpse can filter results by age; for example, asking
to look at only files that are at most 5 days old.
.TP
.B \-T
builds the turbo file.  Starting at version 3.0, this is the default,
so using this option has no effect.
.TP
.B \-w k
Glimpseindex does a reasonable, but not a perfect, job of determining
which files should not be indexed.
Sometimes a large text file should not be indexed; for
example, a dictionary may match most queries.
The -w option stores in a file called .glimpse_messages (in the same
directory as the index) the list of all files that contribute
at least \fIk\fP new words to the index.  The user can look at this list
of files and decide which should or should not be indexed.
The file .glimpse_exclude contains files that will not be indexed
(see more below).  We recommend to set \fIk\fP to about 1000.
This is not an exact measure.  For example, if the same file appears
twice, then the second copy will not contribute any new words
to the dictionary (but if you exclude the first copy and index again,
the second copy will contribute).
.TP
.B \-X
(starting at version 4.0B1) Extract titles from HTML pages and add
the titles to the index (in .glimpse_filenames).
(This feature was added to improve the performance of WebGlimpse.)
Works only on files whose names end with .html, .htm, .shtml, 
and .shtm. 
(see glimpse.h/EXTRACT_INFO_SUFFIX to add to these suffixes.)
The routine to extract titles is called extract_info, in index/filetype.c. 
This feature can be modified in various ways to extract 
info from many filetypes.
The titles are appended to the corresponding filenames with a space
separator.
Glimpseindex assumes that filenames don't have spaces in them.
.TP
.B \-z
Allow customizable filtering, using the file .glimpse_filters 
to perform the programs listed there for each match.  The best example is
compress/decompress.  If .glimpse_filters include the line
.br
*.Z   uncompress <
.br
(separated by tabs)
then before indexing any file that matches the pattern "*.Z" (same
syntax as the one for .glimpse_exclude) the command listed is
executed first (assuming input is from stdin, which is why uncompress
needs <) and its output (assuming it goes to stdout) is indexed.
The file itself is not changed (i.e., it stays compressed).
Then if glimpse -z is used, the same program is used on these files
on the fly.  Any program can be used (we run 'exec').  For example,
one can filter out parts of files that should not be indexed.
Glimpseindex tries to apply all filters in .glimpse_filters in the
order they are given.
For example, if you want to uncompress a file and then extract
some part of it, put the compression command (the example above)
first and then another line that specifies the extraction.
Note that this can slow down the search because the filters need to
be run before files are searched.
.SH "GLIMPSEINDEX FILES"
.LP
All files used by glimpse are located at the directory(ies) where 
the index(es) is (are) stored and have .glimpse_ as a prefix.
The first two files (.glimpse_exclude and .glimpse_include) are
optionally supplied by the user.  The other files are built and
read by glimpse.
.LP
.IP "\fB.glimpse_exclude\fR"
contains a list of files that glimpseindex is explicitly told to ignore.  
In general, the syntax of .glimpse_exclude/include is the same as
that of agrep (or any other grep).  The lines in the .glimpse_exclude
file are matched to the file names, and if they match, the files 
are excluded.  Notice that agrep matches to parts of the string!
e.g., agrep /ftp/pub will match /home/ftp/pub and /ftp/pub/whatever.
So, if you want to exclude /ftp/pub/core, you just list
it, as is, in the .glimpse_exclude file.
If you put "/home/ftp/pub/cdrom" in .glimpse_exclude, every file
name that matches that string will be excluded, meaning all files
below it.
You can use ^ to indicate the beginning of a file name, and $ to
indicate the end of one, and you can use * and ? in the usual way.
For example /ftp/*html will exclude /ftp/pub/foo.html, but will
also exclude /home/ftp/pub/html/whatever;  if you want to exclude
files that start with /ftp and end with html use ^/ftp*html$
Notice that putting a * at the beginning or at the end is redundant
(in fact, in this case glimpseindex will remove the * when it 
does the indexing).
No other meta characters are allowed in .glimpse_exclude
(e.g., don't use .* or # or |).
Lines with * or ? must have no more than 30 characters.
Notice that, although the index itself will not be indexed,
the list of file names (.glimpse_filenames) will be indexed
unless it is explicitly listed in .glimpse_exclude.
.IP "\fB.glimpse_filters\fR"
See the description above for the -z option.
.IP "\fB.glimpse_include\fR"
contains a list of files that glimpseindex
is explicitly told to \fIinclude\fP in the index even though they may look
like non-text files.  Symbolic links are followed by glimpseindex 
only if they are specifically included here.
The syntax is the same as the one for .glimpse_exclude (see there).
If a file is in both .glimpse_exclude and .glimpse_include it will be
excluded unless -i is used.
.IP "\fB.glimpse_filenames\fP"
contains the list of all indexed file names, one per line.
This is an ASCII file that can also be used with agrep to search
for a file name leading to a fast find command.
For example, 
.br
glimpse 'count#\\.c$' ~/.glimpse_filenames
.br
will output the names of all (indexed) .c files that have 'count' in
their name (including anywhere on the path from the index).
Setting the following alias in the .login file may be useful:
.br
alias findfile 'glimpse -h \!:1 ~/.glimpse_filenames'
.IP ".\fBglimpse_index\fP"
contains the index.  The index consists of lines, each starting with a
word followed by a list of block numbers (unless the -o or -b options 
are used, in which case each word is followed by an offset into 
the file .glimpse_partitions where all pointers are kept).
The block/file numbers are stored in binary form, so this is not an ASCII file.
.IP "\fB.glimpse_messages\fP"
contains the output of the -w option (see above).
.IP "\fB.glimpse_partitions\fP"
contains the partition of the indexed space into blocks
and, when the index is built with the -o or -b options, some part of the
index.  This file is used internally by glimpse and it is
a non-ASCII file.
.IP "\fB.glimpse_statistics\fP"
contains some statistics about the makeup of the index.  Useful for
some advanced applications and customization of glimpse.
.SH "STRUCTURED QUERIES"
Glimpse can search for Boolean combinations of "attribute=value" terms
by using the Harvest SOIF parser library (in glimpse/libtemplate). 
To search this way, the index must be made by using the -s option of
glimpseindex (this can be used in conjunction with other glimpseindex
options). For glimpse and glimpseindex to recognize "structured" files,
they must be in SOIF format. In this format, each value is prefixed by
an attribute-name with the size of the value (in bytes) present in "{}"
after the name of the attribute.  
For example, The following lines are part of an SOIF file:
.br
.nf
type{17}:       Directory-Listing
md5{32}:        3858c73d68616df0ed58a44d306b12ba
.fi
Any string can serve as an attribute name.
Glimpse "pattern;type=Directory-Listing" will search for "pattern"
only in files whose type is "Directory-Listing".
The file itself is considered to be
one "object" and its name/url appears as the first attribute with an
"@" prefix; e.g.,
@FILE { http://xxx... }
The scope of Boolean operations changes from records
(lines) to whole files when structured queries are used in glimpse
(since individual query terms can look at different attributes and they
may not be "covered" by the record/line).  Note that glimpse can only
search for patterns in the value parts of the SOIF file: there are some 
attributes (like the TTL, MD5, etc.) that are interpreted by Harvest's
internal routines.
See http://harvest.cs.colorado.edu/harvest/user-manual/ for more detailed
information of the SOIF format.
.SH "REFERENCES"
.IP 1.
U. Manber and S. Wu,
"GLIMPSE: A Tool to Search Through Entire File Systems,"
\fIUsenix Winter 1994 Technical Conference\fP
(best paper award),
San Francisco (January 1994), pp. 23\-32.
Also, Technical Report #TR 93-34, Dept. of Computer Science,
University of Arizona, October 1993 (a postscript file
is available by anonymous ftp at
ftp://ftp.cs.arizona.edu/reports/1993/TR93-34.ps).
.IP 2.
S. Wu and U. Manber,
"Fast Text Searching Allowing Errors,"
\fICommunications of the ACM\fP
\fB35\fP (October 1992), pp. 83\-91.
.SH "SEE ALSO"
.BR agrep (1),
.BR ed (1),
.BR ex (1),
.BR glimpse (1),
.BR glimpseserver (1),
.BR grep (1V),
.BR sh (1),
.BR csh (1).
.SH LIMITATIONS
.LP
The index of glimpse is word based.  A pattern that contains more than
one word cannot be found in the index.  The way glimpse overcomes this
weakness is by splitting any multi-word pattern into its set of words
and looking for all of them in the index.
For example, \fBglimpse 'linear programming'\fR will first consult the index
to find all files containing both \fIlinear\fP and \fIprogramming\fP,
and then apply agrep to find the combined pattern.
This is usually an effective solution, but it can be slow for
cases where both words are very common, but their combination is not.
.LP
The index of glimpse stores all patterns in lower case.
When glimpse searches the index it first converts
all patterns to lower case, finds the appropriate files,
and then searches the actual files using the original
patterns.
So, for example, \fIglimpse ABCXYZ\fR will first find all
files containing abcxyz in any combination of lower and upper
cases, and then searches these files directly, so only the
right cases will be found.
One problem with this approach is discovering misspellings
that are caused by wrong cases.
For example, \fIglimpse -B abcXYZ\fR will first search the
index for the best match to abcxyz (because the pattern is
converted to lower case); it will find that there are matches
with no errors, and will go to those files to search them
directly, this time with the original upper cases. 
If the closest match is, say AbcXYZ, glimpse may miss it,
because it doesn't expect an error.
Another problem is speed.  If you search for "ATT", it will look
at the index for "att".  Unless you use -w to match the whole word,
glimpse may have to search all files containing, for example, "Seattle"
which has "att" in it.
.LP
There is no size limit for simple patterns and simple patterns
with Boolean AND or OR.
More complicated patterns 
are currently limited to approximately 30 characters.
Lines are limited to 1024 characters.
Records are limited to 48K, and may be truncated if they are larger
than that.
The limit of record length can be 
changed by modifying the parameter Max_record in agrep.h.
.LP
Each line in .glimpse_exclude or .glimpse_include that contains 
a * or a ? must not exceed 30 characters length.
.LP
Glimpseindex does not index words of size > 64.
.LP
A medium-size index (-b) may lead to actually slower query times
if the files are all very small.
.LP
Under -b, it may be impossible to make the stop list empty.
Glimpseindex is using the "sort" routine, and all occurrences
of a word appear at some point on one line.
Sort is limiting the size of lines it can handle (the value depends
on the platform; ours is 16KB).
If the lines are too big, the word is added to the stop list.
.SH BUGS
.LP
Please send bug reports or comments to [e-mail].
.SH DIAGNOSTICS
(Only in version 3.6 and above.)
.br
exit status 0: terminated normally;
.br
exit status 1: glimpseindex errors (e.g., bad option combos, no files were
indexed, etc.)
.br
exit status 2: system errors (e.g., write failed, sort failed, malloc failed).
.SH AUTHORS
Udi Manber and Burra Gopal, Department of Computer Science, 
University of Arizona, and Sun Wu, the National Chung-Cheng University,
Taiwan. (Email:  [e-mail])