Saturday, February 12, 2000
This is File::Sort 0.91, for sorting files similarly to sort(1). Written
primarily for MacPerl users who do not have sort(1) and because of memory
limitations cannot sort files in memory, but works on all perls, and can
be useful for portable sorting of large files, or for any system that
doesn't have a sort(1) and it memory-deprived (including Windows).
***WARNING***
Complete rewrite from 0.1x. Took the code from this module to write sort
utility for PPT project, then brought changes back over. As a result the
interface has changed slightly, mostly in regard to what letters are
used for options, but there are also some key behavioral differences. If
you need the old interface, the old module will remain on CPAN, but will
not be supported. Sorry for any inconvenience this may cause. The good
news is that it should not be too difficult to update your code to use
the new interface. Almost all the functionality remains, and mostly
only letters signifying various options changed.
***WARNING***
See HISTORY below for changes.
This archive can always be obtained from:
http://perl.com/CPAN/authors/id/CNANDOR/
http://perl.com/CPAN/modules/by-module/File/
Mac users: The file is a tarred, gzipped file. Use Stuffit Expander
or a similar program (like my cpan-mac stuff, also in the CNANDOR
directory) to get at the archive.
Please let me know how well it does(n't) work, and any changes you'd
like to see.
The sort.pudge program in eg/ does not actually use the File::Sort
module; the actual File::Sort module sources are included in the
program itself, as it is written for distribution with the PPT
project .
#=======================================================================
NAME
File::Sort - Sort a file or merge sort multiple files
SYNOPSIS
use File::Sort qw(sort_file);
sort_file({
I => [qw(file_1 file_2)],
o => 'file_new', k => '5.3,5.5rn', -t => '|'
});
sort_file('file1', 'file1.sorted');
DESCRIPTION
***DANGER, WILL ROBINSON***
The interface has changed in some significant ways from 0.1x. See the
section on "HISTORY".
This module sorts text files by lines (or records). Comparisons are
based on one or more sort keys extracted from each line of input, and
are performed lexicographically. By default, if keys are not given,
sort regards each input line as a single field. The sort is a merge
sort. If you don't like that, feel free to change it.
Options
The following options are available, and are passed in the hash
reference passed to the function in the format:
OPTION => VALUE
Where an option can take multiple values (like `I', `k', and `pos'),
values may be passed via an anonymous array:
OPTION => [VALUE1, VALUE2]
Where the OPTION is a switch, it should be passed a boolean VALUE of 1
or 0.
This interface will always be supported, though a more perlish
interface may be offered in the future, as well. This interface is
basically a mapping of the command-line options to the Unix sort
utility.
`I' *INPUT*
Pass in the input file(s). This can be either a single string with
the filename, or an array reference containing multiple filename
strings.
`c' Check that single input fle is ordered as specified by the arguments
and the collating sequence of the current locale. No output is
produced; only the exit code is affected.
`m' Merge only; the input files are assumed to already be sorted.
`o' *OUTPUT*
Specify the name of an *OUTPUT* file to be used instead of the
standard output.
`u' Unique: Suppresses all but one in each set of lines having equal keys.
If used with the c option check that there are no lines with
consecutive lines with duplicate keys, in addition to checking
that the input file is sorted.
`y' *MAX_SORT_RECORDS*
Maximum number of lines (records) read before writing to temp
file. Default is 200,000. This may eventually change to be kbytes
instead of lines. Lines was easier to implement. Can also specify
with MAX_SORT_RECORDS environment variable.
`F' *MAX_SORT_FILES*
Maximum number of temp files to be held open at once. Default to
40, as older Windows ports had quite a small limit. Can also
specify with MAX_SORT_FILES environment variable. No temp files
will be used at all if MAX_SORT_RECORDS is never reached.
`D' Send debugging information to STDERR. Behavior subject to change.
The following options override the default ordering rules. When
ordering options appear independent of any key field specifications,
the requested field ordering rules are applied globally to all sort
keys. When attached to a specific key (see k), the specified ordering
options override all global ordering options for that key.
`d' Specify that only blank characters and alphanumeric characters,
according to the current locale setting, are significant in
comparisons. d overrides i.
`f' Consider all lower-case characters that have upper-case equivalents,
according to the current locale setting, to be the upper-case
equivalent for the purposes of comparison.
`i' Ignores all characters that are non-printable, according to the
current locale setting.
`n' Does numeric instead of string compare, using whatever perl considers
to be a number in numeric comparisons.
`r' Reverse the sense of the comparisons.
`b' Ignore leading blank characters when determining the starting and
ending positions of a restricted sort key. If the b option is
specified before the first k option, it is applied to all k
options. Otherwise, the b option can be attached indepently to
each field_start or field_end option argument (see below).
`t' *STRING*
Use *STRING* as the field separator character; char is not
considered to be part of a field (although it can be included in a
sort key). Each occurrence of char is significant (for example,
delimits an empty field). If t is not specified,
blank characters are used as default field separators; each
maximal non-empty sequence of blank characters that follows a non-
blank character is a field separator.
`X' *STRING*
Same as t, but *STRING* is interpreted as a Perl regular
expression instead. Do not escape any characters (`/' characters
need to be escaped internally, and will be escaped for you).
The string matched by *STRING* is not included in the fields
themselves, unless demanded by perl's regex and split semantics
(e.g., regexes in parentheses will add that matched expression as
an extra field). See the perlre manpage and the "split" entry in
the perlfunc manpage.
`R' *STRING*
Record separator, defaults to newline.
`k' *pos1[,pos2]*
The keydef argument is a restricted sort key field definition. The
format of this definition is:
field_start[.first_char][type][,field_end[.last_char][type]]
where field_start and field_end define a key field restricted to a
portion of the line, and type is a modifier from the list of
characters b, d, f, i, n, r. The b modifier behaves like the b
option, but applies only to the field_start or field_end to which
it is attached. The other modifiers behave like the corresponding
options, but apply only to the key field to which they are
attached; they have this effect if specified with field_start,
field_end, or both. If any modifier is attached to a field_start
or a field_end, no option applies to either.
Occurrences of the k option are significant in command line order.
If no k option is specified, a default sort key of the entire line
is used. When there are multiple keys fields, later keys are
compared only after all earlier keys compare equal.
Except when the u option is specified, lines that otherwise
compare equal are ordered as if none of the options d, f, i, n or
k were present (but with r still in effect, if it was specified)
and with all bytes in the lines significant to the comparison. The
order in which lines that still compare equal are written is
unspecified.
`pos' *+pos1 [-pos2]*
Similar to k, these are mostly obsolete switches, but some people
like them and want to use them. Usage is:
+field_start[.first_char][type] [-field_end[.last_char][type]]
Where field_end in k specified the last position to be included,
it specifes the last position to NOT be included. Also, numbers
are counted from 0 instead of 1. pos2 must immediately follow
corresponding +pos1. The rest should be the same as the k option.
Mixing +pos1 pos2 with k is allowed, but will result in all of the
+pos1 pos2 options being ordered AFTER the k options. It is best
if you Don't Do That. Pick one and stick with it.
Here are some equivalencies:
pos => '+1 -2' -> k => '2,2'
pos => '+1.1 -1.2' -> k => '2.2,2.2'
pos => ['+1 -2', '+3 -5'] -> k => ['2,2', '4,5']
pos => ['+2', '+0b -1'] -> k => ['3', '1b,1']
pos => '+2.1 -2.4' -> k => '3.2,3.4'
pos => '+2.0 -3.0' -> k => '3.1,4.0'
Not Implemented
If the options are not listed as implemented above, or are not listed
in TODO below, they are not in the plan for implementation. This
includes T and z.
EXAMPLES
Sort file by straight string compare of each line, sending output to
STDOUT.
use File::Sort qw(sort_file);
sort_file('file');
Sort contents of file by second key in file.
sort_file({k => 2, I => 'file'});
Sort, in reverse order, contents of file1 and file2, placing output in
outfile and using second character of second field as the sort key.
sort_file({
r => 1, k => '2.2,2.2', o => 'outfile',
I => ['file1', 'file2']
});
Same sort but sorting numerically on characters 3 through 5 of the
fifth field first, and only return records with unique keys.
sort_file({
u => 1, r => 1, k => ['5.3,5.5rn', '2.2,2.2'],
o => 'outfile', I => ['file1', 'file2']
});
Print passwd(4) file sorted by numeric user ID.
sort_file({t => ':', k => '3n', I => '/etc/passwd'});
For the anal sysadmin, check that passwd(4) file is sorted by numeric
user ID.
sort_file({c => 1, t => ':', k => '3n', I => '/etc/passwd'});
ENVIRONMENT
MAX_SORT_RECORDS
Default is 200,000. Maximum number of records to use before
writing to a temp file. Overriden by y option.
MAX_SORT_FILES
Maximum number of open temp files to use before merging open temp
files. Overriden by F option.
LC_COLLATE
Determine the locale for ordering rules.
LC_CTYPE
Determine the locale for the interpretation of sequences of bytes
of text data as characters (for example, single- versus multi-byte
characters in arguments and input files) and the behaviour of
character classification for the b, d, f, i and n options.
EXPORT
Exports `sort_file' on request.
TODO
Better debugging and error reporting
Performance hit with -u
Do bytes instead of lines
Tests fail on non-ASCII locales.
HISTORY
v0.91, Saturday, February 12, 2000
Closed all files in test.pl so they could be unlinked on some
platforms. (Hubert Toullec)
Documented `I' option. (Hubert Toullec)
Removed O_EXCL flag from `sort_file'.
Fixed bug in sorting multiple files. (Paul Eckert)
v0.90, Friday, April 30, 1999
Complete rewrite. Took the code from this module to write sort
utility for PPT project, then brought changes back over. As a
result the interface has changed slightly, mostly in regard to
what letters are used for options, but there are also some key
behavioral differences. If you need the old interface, the old
module will remain on CPAN, but will not be supported. Sorry for
any inconvenience this may cause. The good news is that it should
not be too difficult to update your code to use the new interface.
v0.20
Fixed bug with unique option (didn't work :).
Switched to sysopen for better portability.
Print to STDOUT if no output file supplied.
Added c option to check sorting.
v0.18 (31 January 1998)
Tests 3 and 4 failed because we hit the open file limit in the
standard Windows port of perl5.004_02 (50). Adjusted the default
for total number of temp files from 50 to 40 (leave room for other
open files), changed docs. (Mike Blazer, Gurusamy Sarathy)
v0.17 (30 December 1998)
Fixed bug in `_merge_files' that tried to `open' a passed
`IO::File' object.
Fixed up docs and did some more tests and benchmarks.
v0.16 (24 December 1998)
One year between releases was too long. I made changes Miko
O'Sullivan wanted, and I didn't even know I had made them.
Also now use `IO::File' to create temp files, so the TMPDIR option
is no longer supported. Hopefully made the whole thing more robust
and faster, while supporting more options for sorting, including
delimited sorts, and arbitrary sorts.
Made CHUNK default a lot larger, which improves performance. On
low-memory systems, or where (e.g.) the MacPerl binary is not
allocated much RAM, it might need to be lowered.
v0.11 (04 January 1998)
More cleanup; fixed special case of no linebreak on last line;
wrote test suite; fixed warning for redefined subs (sort1 and
sort2).
v0.10 (03 January 1998)
Some cleanup; made it not subject to system file limitations;
separated many parts out into separate functions.
v0.03 (23 December 1997)
Added reverse and numeric sorting options.
v0.02 (19 December 1997)
Added unique and merge-only options.
v0.01 (18 December 1997)
First release.
THANKS
Mike Blazer , Vicki Brown , Tom
Christiansen , Albert Dvornik , Paul
Eckert , Gene Hsu , Andrew
M. Langmead , Brian L. Matthews ,
Rich Morin , Matthias Neeracher ,
Miko O'Sullivan , Tom Phoneix ,
Gurusamy Sarathy Hubert Toullec
.
AUTHOR
Chris Nandor , http://pudge.net/
Copyright (c) 2000 Chris Nandor. All rights reserved. This program is
free software; you can redistribute it and/or modify it under the
terms of the Artistic License, distributed with Perl.
VERSION
v0.91, Saturday, February 12, 2000
SEE ALSO
sort(1), locale, PPT project, .
#=======================================================================