1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
|
<?xml version="1.0" encoding="utf-8" ?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<meta name="generator" content="Docutils 0.4.1: http://docutils.sourceforge.net/" />
<title>UNIPATH</title>
<meta name="author" content="Mike Orr <sluggoster@gmail.com>" />
<style type="text/css">
/*
:Author: David Goodger
:Contact: goodger@users.sourceforge.net
:Date: $Date: 2005-12-18 01:56:14 +0100 (Sun, 18 Dec 2005) $
:Revision: $Revision: 4224 $
:Copyright: This stylesheet has been placed in the public domain.
Default cascading style sheet for the HTML output of Docutils.
See http://docutils.sf.net/docs/howto/html-stylesheets.html for how to
customize this style sheet.
*/
/* used to remove borders from tables and images */
.borderless, table.borderless td, table.borderless th {
border: 0 }
table.borderless td, table.borderless th {
/* Override padding for "table.docutils td" with "! important".
The right padding separates the table cells. */
padding: 0 0.5em 0 0 ! important }
.first {
/* Override more specific margin styles with "! important". */
margin-top: 0 ! important }
.last, .with-subtitle {
margin-bottom: 0 ! important }
.hidden {
display: none }
a.toc-backref {
text-decoration: none ;
color: black }
blockquote.epigraph {
margin: 2em 5em ; }
dl.docutils dd {
margin-bottom: 0.5em }
/* Uncomment (and remove this text!) to get bold-faced definition list terms
dl.docutils dt {
font-weight: bold }
*/
div.abstract {
margin: 2em 5em }
div.abstract p.topic-title {
font-weight: bold ;
text-align: center }
div.admonition, div.attention, div.caution, div.danger, div.error,
div.hint, div.important, div.note, div.tip, div.warning {
margin: 2em ;
border: medium outset ;
padding: 1em }
div.admonition p.admonition-title, div.hint p.admonition-title,
div.important p.admonition-title, div.note p.admonition-title,
div.tip p.admonition-title {
font-weight: bold ;
font-family: sans-serif }
div.attention p.admonition-title, div.caution p.admonition-title,
div.danger p.admonition-title, div.error p.admonition-title,
div.warning p.admonition-title {
color: red ;
font-weight: bold ;
font-family: sans-serif }
/* Uncomment (and remove this text!) to get reduced vertical space in
compound paragraphs.
div.compound .compound-first, div.compound .compound-middle {
margin-bottom: 0.5em }
div.compound .compound-last, div.compound .compound-middle {
margin-top: 0.5em }
*/
div.dedication {
margin: 2em 5em ;
text-align: center ;
font-style: italic }
div.dedication p.topic-title {
font-weight: bold ;
font-style: normal }
div.figure {
margin-left: 2em ;
margin-right: 2em }
div.footer, div.header {
clear: both;
font-size: smaller }
div.line-block {
display: block ;
margin-top: 1em ;
margin-bottom: 1em }
div.line-block div.line-block {
margin-top: 0 ;
margin-bottom: 0 ;
margin-left: 1.5em }
div.sidebar {
margin-left: 1em ;
border: medium outset ;
padding: 1em ;
background-color: #ffffee ;
width: 40% ;
float: right ;
clear: right }
div.sidebar p.rubric {
font-family: sans-serif ;
font-size: medium }
div.system-messages {
margin: 5em }
div.system-messages h1 {
color: red }
div.system-message {
border: medium outset ;
padding: 1em }
div.system-message p.system-message-title {
color: red ;
font-weight: bold }
div.topic {
margin: 2em }
h1.section-subtitle, h2.section-subtitle, h3.section-subtitle,
h4.section-subtitle, h5.section-subtitle, h6.section-subtitle {
margin-top: 0.4em }
h1.title {
text-align: center }
h2.subtitle {
text-align: center }
hr.docutils {
width: 75% }
img.align-left {
clear: left }
img.align-right {
clear: right }
ol.simple, ul.simple {
margin-bottom: 1em }
ol.arabic {
list-style: decimal }
ol.loweralpha {
list-style: lower-alpha }
ol.upperalpha {
list-style: upper-alpha }
ol.lowerroman {
list-style: lower-roman }
ol.upperroman {
list-style: upper-roman }
p.attribution {
text-align: right ;
margin-left: 50% }
p.caption {
font-style: italic }
p.credits {
font-style: italic ;
font-size: smaller }
p.label {
white-space: nowrap }
p.rubric {
font-weight: bold ;
font-size: larger ;
color: maroon ;
text-align: center }
p.sidebar-title {
font-family: sans-serif ;
font-weight: bold ;
font-size: larger }
p.sidebar-subtitle {
font-family: sans-serif ;
font-weight: bold }
p.topic-title {
font-weight: bold }
pre.address {
margin-bottom: 0 ;
margin-top: 0 ;
font-family: serif ;
font-size: 100% }
pre.literal-block, pre.doctest-block {
margin-left: 2em ;
margin-right: 2em ;
background-color: #eeeeee }
span.classifier {
font-family: sans-serif ;
font-style: oblique }
span.classifier-delimiter {
font-family: sans-serif ;
font-weight: bold }
span.interpreted {
font-family: sans-serif }
span.option {
white-space: nowrap }
span.pre {
white-space: pre }
span.problematic {
color: red }
span.section-subtitle {
/* font-size relative to parent (h1..h6 element) */
font-size: 80% }
table.citation {
border-left: solid 1px gray;
margin-left: 1px }
table.docinfo {
margin: 2em 4em }
table.docutils {
margin-top: 0.5em ;
margin-bottom: 0.5em }
table.footnote {
border-left: solid 1px black;
margin-left: 1px }
table.docutils td, table.docutils th,
table.docinfo td, table.docinfo th {
padding-left: 0.5em ;
padding-right: 0.5em ;
vertical-align: top }
table.docutils th.field-name, table.docinfo th.docinfo-name {
font-weight: bold ;
text-align: left ;
white-space: nowrap ;
padding-left: 0 }
h1 tt.docutils, h2 tt.docutils, h3 tt.docutils,
h4 tt.docutils, h5 tt.docutils, h6 tt.docutils {
font-size: 100% }
tt.docutils {
background-color: #eeeeee }
ul.auto-toc {
list-style-type: none }
</style>
</head>
<body>
<div class="document" id="unipath">
<h1 class="title">UNIPATH</h1>
<h2 class="subtitle" id="an-object-oriented-approach-to-file-directory-operations">An object-oriented approach to file/directory operations</h2>
<table class="docinfo" frame="void" rules="none">
<col class="docinfo-name" />
<col class="docinfo-content" />
<tbody valign="top">
<tr><th class="docinfo-name">Version:</th>
<td>0.2.0 (2008-05-17)</td></tr>
<tr class="field"><th class="docinfo-name">Home page:</th><td class="field-body"><a class="reference" href="http://sluggo.scrapping.cc/python/unipath/">http://sluggo.scrapping.cc/python/unipath/</a></td>
</tr>
<tr><th class="docinfo-name">Author:</th>
<td>Mike Orr <<a class="reference" href="mailto:sluggoster@gmail.com">sluggoster@gmail.com</a>></td></tr>
<tr class="field"><th class="docinfo-name">License:</th><td class="field-body">Python (<a class="reference" href="http://www.python.org/psf/license">http://www.python.org/psf/license</a>)</td>
</tr>
<tr class="field"><th class="docinfo-name">Based on:</th><td class="field-body">See HISTORY section below.</td>
</tr>
</tbody>
</table>
<!-- To format this document as HTML:
rst2html.py README.txt README.html -->
<div class="contents topic">
<p class="topic-title first"><a id="contents" name="contents">Contents</a></p>
<ul class="simple">
<li><a class="reference" href="#introduction" id="id7" name="id7">Introduction</a></li>
<li><a class="reference" href="#installation-and-testing" id="id8" name="id8">Installation and testing</a></li>
<li><a class="reference" href="#path-and-abstractpath-objects" id="id9" name="id9">Path and AbstractPath objects</a><ul>
<li><a class="reference" href="#constructor" id="id10" name="id10">Constructor</a></li>
<li><a class="reference" href="#normalization" id="id11" name="id11">Normalization</a></li>
<li><a class="reference" href="#properties" id="id12" name="id12">Properties</a></li>
<li><a class="reference" href="#methods" id="id13" name="id13">Methods</a></li>
</ul>
</li>
<li><a class="reference" href="#path-objects-only" id="id14" name="id14">Path objects only</a><ul>
<li><a class="reference" href="#note-on-arguments" id="id15" name="id15">Note on arguments</a></li>
<li><a class="reference" href="#current-directory" id="id16" name="id16">Current directory</a></li>
<li><a class="reference" href="#calculating-paths" id="id17" name="id17">Calculating paths</a></li>
<li><a class="reference" href="#listing-directories" id="id18" name="id18">Listing directories</a></li>
<li><a class="reference" href="#file-attributes-and-permissions" id="id19" name="id19">File attributes and permissions</a></li>
<li><a class="reference" href="#modifying-paths" id="id20" name="id20">Modifying paths</a><ul>
<li><a class="reference" href="#creating-renaming-removing" id="id21" name="id21">Creating/renaming/removing</a></li>
<li><a class="reference" href="#symbolic-and-hard-links" id="id22" name="id22">Symbolic and hard links</a></li>
</ul>
</li>
<li><a class="reference" href="#high-level-operations" id="id23" name="id23">High-level operations</a></li>
</ul>
</li>
<li><a class="reference" href="#tools" id="id24" name="id24">Tools</a><ul>
<li><a class="reference" href="#dict2dir" id="id25" name="id25">dict2dir</a></li>
</ul>
</li>
<li><a class="reference" href="#non-native-paths" id="id26" name="id26">Non-native paths</a></li>
<li><a class="reference" href="#history" id="id27" name="id27">History</a></li>
<li><a class="reference" href="#comparision-with-os-os-path-shutil-and-path-py" id="id28" name="id28">Comparision with os/os.path/shutil and path.py</a></li>
<li><a class="reference" href="#design-decisions-open-issues" id="id29" name="id29">Design decisions / open issues</a></li>
</ul>
</div>
<div class="section">
<h1><a class="toc-backref" href="#id7" id="introduction" name="introduction">Introduction</a></h1>
<p>Unipath is an object-oriented front end to the file/directory functions
scattered throughout several Python library modules. It's based on Jason
Orendorff's <em>path.py</em> but does not adhere as strictly to the underlying
functions' syntax, in order to provide more user convenience and higher-level
functionality. It comes with a test suite.</p>
<div class="important">
<p class="first admonition-title">Important</p>
<p>Changes for Unipath 0.1.0 users</p>
<p class="last"><tt class="docutils literal"><span class="pre">Path</span></tt> has been renamed to <tt class="docutils literal"><span class="pre">AbstractPath</span></tt>, and <tt class="docutils literal"><span class="pre">FSPath</span></tt> to <tt class="docutils literal"><span class="pre">Path</span></tt>.
<tt class="docutils literal"><span class="pre">FSPath</span></tt> remains as an alias for backward compatibility.
<tt class="docutils literal"><span class="pre">Path.symlink()</span></tt> is gone; use <tt class="docutils literal"><span class="pre">Path.write_link()</span></tt> instead. (Note that
the argument order is the opposite.) See CHANGES.txt for the complete list
of changes.</p>
</div>
<p>The <tt class="docutils literal"><span class="pre">Path</span></tt> class encapsulates the file/directory operations in Python's
<tt class="docutils literal"><span class="pre">os</span></tt>, <tt class="docutils literal"><span class="pre">os.path</span></tt>, and <tt class="docutils literal"><span class="pre">shutil</span></tt> modules.</p>
<p>Its superclass <tt class="docutils literal"><span class="pre">AbstractPath</span></tt> class encapsulates those operations which
aren't dependent on the filesystem. This is mainly an academic distinction to
keep the code clean. Since <tt class="docutils literal"><span class="pre">Path</span></tt> can do everything <tt class="docutils literal"><span class="pre">AbstractPath</span></tt> does,
most users just use <tt class="docutils literal"><span class="pre">Path</span></tt>.</p>
<p>The API has been streamlined to focus on what the application developer wants
to do rather than on the lowest-level operations; e.g., <tt class="docutils literal"><span class="pre">.mkdir()</span></tt> succeeds
silently if the directory already exists, and <tt class="docutils literal"><span class="pre">.rmtree()</span></tt> doesn't barf if the
target is a file or doesn't exist. This allows the developer to write simple
calls that "just work" rather than entire if-stanzas to handle low-level
details s/he doesn't care about. This makes applications more self-documenting
and less cluttered.</p>
<p>Convenience methods:</p>
<blockquote>
<ul class="simple">
<li><tt class="docutils literal"><span class="pre">.read_file</span></tt> and <tt class="docutils literal"><span class="pre">.write_file</span></tt> encapsulate the open/read/close pattern.</li>
<li><tt class="docutils literal"><span class="pre">.needs_update(others)</span></tt> tells whether the path needs updating; i.e.,
if it doesn't exist or is older than any of the other paths.</li>
<li><tt class="docutils literal"><span class="pre">.ancestor(N)</span></tt> returns the Nth parent directory, useful for joining paths.</li>
<li><tt class="docutils literal"><span class="pre">.child(\*components)</span></tt> is a "safe" version of join.</li>
<li><tt class="docutils literal"><span class="pre">.split_root()</span></tt> handles slash/drive/UNC absolute paths in a uniform way.</li>
</ul>
</blockquote>
<ul class="simple">
<li>Optional high-level functions in the <tt class="docutils literal"><span class="pre">unipath.tools</span></tt> module.</li>
<li>For Python >= 2.4</li>
<li>Path objects are immutable so can be used as dictionary keys.</li>
</ul>
<p>Sample usage for pathname manipulation:</p>
<pre class="literal-block">
>>> from unipath import Path
>>> p = Path("/usr/lib/python2.5/gopherlib.py")
>>> p.parent
Path("/usr/lib/python2.5")
>>> p.name
Path("gopherlib.py")
>>> p.ext
'.py'
>>> p.stem
Path('gopherlib')
>>> q = Path(p.parent, p.stem + p.ext)
>>> q
Path('/usr/lib/python2.5/gopherlib.py')
>>> q == p
True
</pre>
<p>Sample usage for filesystem access:</p>
<pre class="literal-block">
>>> import tempfile
>>> from unipath import Path
>>> d = Path(tempfile.mkdtemp())
>>> d.isdir()
True
>>> p = Path(d, "sample.txt")
>>> p.exists()
False
>>> p.write_file("The king is a fink!")
>>> p.exists()
True
>>> print p.read_file()
The king is a fink!
>>> d.rmtree()
>>> p.exists()
False
</pre>
<p>The name "Unipath" is short for "universal path", as it grew out of a
discussion on python-dev about the ideal path API for Python.</p>
<p>Unipath's API is mostly stable but there's no guarantee it won't change in
future versions.</p>
</div>
<div class="section">
<h1><a class="toc-backref" href="#id8" id="installation-and-testing" name="installation-and-testing">Installation and testing</a></h1>
<p>If you have EasyInstall, run "easy_install unipath". Otherwise unpack the
source and run "python setup.py install" in the top-level directory.
You can also copy the "unipath" directory to somewhere on your Python
path.</p>
<p>To test the library you'll need the Nose package. cd to the top-level
directory and run "python unipath/test.py".</p>
</div>
<div class="section">
<h1><a class="toc-backref" href="#id9" id="path-and-abstractpath-objects" name="path-and-abstractpath-objects">Path and AbstractPath objects</a></h1>
<div class="section">
<h2><a class="toc-backref" href="#id10" id="constructor" name="constructor">Constructor</a></h2>
<p><tt class="docutils literal"><span class="pre">Path</span></tt> (and <tt class="docutils literal"><span class="pre">AbstractPath</span></tt>) objects can be created from a string path, or
from several string arguments which are joined together a la <tt class="docutils literal"><span class="pre">os.path.join</span></tt>.
Each argument can be a string, an <tt class="docutils literal"><span class="pre">(Abstract)Path</span></tt> instance, an int or long,
or a list/tuple of strings to be joined:</p>
<pre class="literal-block">
p = Path("foo/bar.py") # A relative path
p = Path("foo", "bar.py") # Same as previous
p = Path(["foo", "bar.py"]) # Same as previous
p = Path("/foo", "bar", "baz.py") # An absolute path: /foo/bar/baz.py
p = Path("/foo", Path("bar/baz.py")) # Same as previous
p = Path("/foo", ["", "bar", "baz.py"]) # Embedded Path.components() result
p = Path("record", 123) # Same as Path("record/123")
p = Path("") # An empty path
p = Path() # Same as Path(os.curdir)
</pre>
<p>To get the actual current directory, use <tt class="docutils literal"><span class="pre">Path.cwd()</span></tt>. (This doesn't work
with <tt class="docutils literal"><span class="pre">AbstractPath</span></tt>, of course.</p>
<p>Adding two paths results in a concatenated path. The other string methods
return strings, so you'll have to wrap them in <tt class="docutils literal"><span class="pre">Path</span></tt> to make them paths
again. A future version will probably override these methods to return paths.
Multiplying a path returns a string, as if you'd ever want to do that.</p>
</div>
<div class="section">
<h2><a class="toc-backref" href="#id11" id="normalization" name="normalization">Normalization</a></h2>
<p>The new path is normalized to clean up redundant ".." and "." in the
middle, double slashes, wrong-direction slashes, etc. On
case-insensitive filesystems it also converts uppercase to lowercase.
This is all done via <tt class="docutils literal"><span class="pre">os.path.normpath()</span></tt>. Here are some examples
of normalizations:</p>
<pre class="literal-block">
a//b => a/b
a/../b => b
a/./b => a/b
a/b => a\\b # On NT.
a\\b.JPG => a\\b.jpg # On NT.
</pre>
<p>If the actual filesystem path contains symbolic links, normalizing ".." goes to
the parent of the symbolic link rather than to the parent of the linked-to
file. For this reason, and because there may be other cases where normalizing
produces the wrong path, you can disable automatic normalization by setting the
<tt class="docutils literal"><span class="pre">.auto_norm</span></tt> class attribute to false. I'm not sure whether Unipath should
normalize by default, so if you care one way or the other you should explicitly
set it at the beginning of your application. You can override the auto_norm
setting by passing "norm=True" or "norm=False" as a keyword argument to the
constructor. You can also call <tt class="docutils literal"><span class="pre">.norm()</span></tt> anytime to manually normalize the
path.</p>
</div>
<div class="section">
<h2><a class="toc-backref" href="#id12" id="properties" name="properties">Properties</a></h2>
<p>Path objects have the following properties:</p>
<dl class="docutils">
<dt>.parent</dt>
<dd>The path without the final component.</dd>
<dt>.name</dt>
<dd>The final component only.</dd>
<dt>.ext</dt>
<dd>The last part of the final component beginning with a dot (e.g., ".gz"), or
"" if there is no dot. This is also known as the extension.</dd>
<dt>.stem</dt>
<dd>The final component without the extension.</dd>
</dl>
<p>Examples are given in the first sample usage above.</p>
</div>
<div class="section">
<h2><a class="toc-backref" href="#id13" id="methods" name="methods">Methods</a></h2>
<p>Path objects have the following methods:</p>
<dl class="docutils">
<dt>.ancestor(N)</dt>
<dd>Same as specifying <tt class="docutils literal"><span class="pre">.parent</span></tt> N times.</dd>
<dt>.child(*components)</dt>
<dd>Join paths in a safe manner. The child components may not contain a path
separator or be curdir or pardir ("." or ".." on Posix). This is to
prevent untrusted arguments from creating a path above the original path's
directory.</dd>
<dt>.components()</dt>
<dd>Return a list of directory components as strings. The first component will
be the root ("/" on Posix, a Windows drive root, or a UNC share) if the
path is absolute, or "" if it's relative. Calling <tt class="docutils literal"><span class="pre">Path(components)</span></tt>,
<tt class="docutils literal"><span class="pre">Path(*components)</span></tt>, or <tt class="docutils literal"><span class="pre">os.path.join(*components)</span></tt> will recreate the
original path.</dd>
<dt>.expand()</dt>
<dd>Same as <tt class="docutils literal"><span class="pre">p.expand_user().expand_vars().norm()</span></tt>. Usually this is all
you need to fix up a path read from a config file.</dd>
<dt>.expand_user()</dt>
<dd>Interpolate "~" and "~user" if the platform allows, and return a new path.</dd>
<dt>.expand_vars()</dt>
<dd>Interpolate environment variables like "$BACKUPS" if the platform allows,
and return a new path.</dd>
<dt>.isabsolute()</dt>
<dd>Is the path absolute?</dd>
<dt>.norm()</dt>
<dd>See Normalization above. Same as <tt class="docutils literal"><span class="pre">os.path.normpath</span></tt>.</dd>
<dt>.norm_case()</dt>
<dd>On case-insensitive platforms (Windows) convert the path to lower case.
On case-sensitive platforms (Unix) leave the path as is. This also turns
forward slashes to backslashes on Windows.</dd>
<dt>.split_root()</dt>
<dd>Split this path at the root and return a tuple of two paths: the root and
the rest of the path. The root is the same as the first subscript of the
<tt class="docutils literal"><span class="pre">.components()</span></tt> result. Calling <tt class="docutils literal"><span class="pre">Path(root,</span> <span class="pre">rest)</span></tt> or
<tt class="docutils literal"><span class="pre">os.path.join(root,</span> <span class="pre">rest)</span></tt> will produce the original path.</dd>
</dl>
<p>Examples:</p>
<pre class="literal-block">
Path("foo/bar.py").components() =>
[Path(""), Path("foo"), Path("bar.py")]
Path("foo/bar.py").split_root() =>
(Path(""), Path("foo/bar.py"))
Path("/foo/bar.py").components() =>
[Path("/"), Path("foo"), Path("bar.py")]
Path("/foo/bar.py").split_root() =>
(Path("/"), Path("foo/bar.py"))
Path("C:\\foo\\bar.py").components() =>
["Path("C:\\"), Path("foo"), Path("bar.py")]
Path("C:\\foo\\bar.py").split_root() =>
("Path("C:\\"), Path("foo\\bar.py"))
Path("\\\\UNC_SHARE\\foo\\bar.py").components() =>
[Path("\\\\UNC_SHARE"), Path("foo"), Path("bar.py")]
Path("\\\\UNC_SHARE\\foo\\bar.py").split_root() =>
(Path("\\\\UNC_SHARE"), Path("foo\\bar.py"))
Path("~/bin").expand_user() => Path("/home/guido/bin")
Path("~timbot/bin").expand_user() => Path("/home/timbot/bin")
Path("$HOME/bin").expand_vars() => Path("/home/guido/bin")
Path("~//$BACKUPS").expand() => Path("/home/guido/Backups")
Path("dir").child("subdir", "file") => Path("dir/subdir/file")
Path("/foo").isabsolute() => True
Path("foo").isabsolute() => False
</pre>
<p>Note: a Windows drive-relative path like "C:foo" is considered absolute by
<tt class="docutils literal"><span class="pre">.components()</span></tt>, <tt class="docutils literal"><span class="pre">.isabsolute()</span></tt>, and <tt class="docutils literal"><span class="pre">.split_root()</span></tt>, even though
Python's <tt class="docutils literal"><span class="pre">ntpath.isabs()</span></tt> would return false.</p>
</div>
</div>
<div class="section">
<h1><a class="toc-backref" href="#id14" id="path-objects-only" name="path-objects-only">Path objects only</a></h1>
<div class="section">
<h2><a class="toc-backref" href="#id15" id="note-on-arguments" name="note-on-arguments">Note on arguments</a></h2>
<p>All arguments that take paths can also take strings.</p>
</div>
<div class="section">
<h2><a class="toc-backref" href="#id16" id="current-directory" name="current-directory">Current directory</a></h2>
<dl class="docutils">
<dt>Path.cwd()</dt>
<dd>Return the actual current directory; e.g., Path("/tmp/my_temp_dir").
This is a class method.</dd>
<dt>.chdir()</dt>
<dd>Make self the current directory.</dd>
</dl>
</div>
<div class="section">
<h2><a class="toc-backref" href="#id17" id="calculating-paths" name="calculating-paths">Calculating paths</a></h2>
<dl class="docutils">
<dt>.resolve()</dt>
<dd>Return the equivalent path without any symbolic links. This normalizes
the path as a side effect.</dd>
<dt>.absolute()</dt>
<dd>Return the absolute equivalent of self. If the path is relative, this
prefixes the current directory; i.e., <tt class="docutils literal"><span class="pre">FSPath(FSPath.cwd(),</span> <span class="pre">p)</span></tt>.</dd>
<dt>.relative()</dt>
<dd>Return an equivalent path relative to the current directory if possible.
This may return a path prefixed with many "../..". If the path is on a
different drive, this returns the original path unchanged.</dd>
<dt>.rel_path_to(other)</dt>
<dd>Return a path from self to other. In other words, return a path for
'other' relative to self.</dd>
</dl>
</div>
<div class="section">
<h2><a class="toc-backref" href="#id18" id="listing-directories" name="listing-directories">Listing directories</a></h2>
<p><em>These methods are experimental and subject to change.</em></p>
<dl class="docutils">
<dt>.listdir(pattern=None, filter=ALL, names_only=False)</dt>
<dd><p class="first">Return the filenames in this directory.</p>
<p>'pattern' may be a glob expression like "*.py".</p>
<p>'filter' may be a function that takes a <tt class="docutils literal"><span class="pre">FSPath</span></tt> and returns true if it
should be included in the results. The following standard filters are
defined in the <tt class="docutils literal"><span class="pre">unipath</span></tt> module:</p>
<blockquote>
<ul class="simple">
<li><tt class="docutils literal"><span class="pre">DIRS</span></tt>: directories only</li>
<li><tt class="docutils literal"><span class="pre">FILES</span></tt>: files only</li>
<li><tt class="docutils literal"><span class="pre">LINKS</span></tt>: symbolic links only</li>
<li><tt class="docutils literal"><span class="pre">FILES_NO_LINKS</span></tt>: files that aren't symbolic links</li>
<li><tt class="docutils literal"><span class="pre">DIRS_NO_LINKS</span></tt>: directories that aren't symbolic links</li>
<li><tt class="docutils literal"><span class="pre">DEAD_LINKS</span></tt>: symbolic links that point to nonexistent files</li>
</ul>
</blockquote>
<p>This method normally returns FSPaths prefixed with 'self'. If
'names_only' is true, it returns the raw filenames as strings without a
directory prefix (same as <tt class="docutils literal"><span class="pre">os.listdir</span></tt>).</p>
<p>If both 'pattern' and 'filter' are specified, only paths that pass both are
included. 'filter' must not be specified if 'names_only' is true.</p>
<p class="last">Paths are returned in sorted order.</p>
</dd>
</dl>
<p>.walk(pattern=None, filter=None, top_down=True)</p>
<blockquote>
<p>Yield <tt class="docutils literal"><span class="pre">FSPath</span></tt> objects for all files and directories under self,
recursing subdirectories. Paths are yielded in sorted order.</p>
<p>'pattern' and 'filter' are the same as for <tt class="docutils literal"><span class="pre">.listdir()</span></tt>.</p>
<p>If 'top_down' is true (default), yield directories before yielding
the items in them. If false, yield the items first.</p>
</blockquote>
</div>
<div class="section">
<h2><a class="toc-backref" href="#id19" id="file-attributes-and-permissions" name="file-attributes-and-permissions">File attributes and permissions</a></h2>
<dl class="docutils">
<dt>.atime()</dt>
<dd>Return the path's last access time.</dd>
<dt>.ctime()</dt>
<dd>Return the path's ctime. On Unix this returns the time the path's
permissions and ownership were last modified. On Windows it's the path
creation time.</dd>
<dt>.exists()</dt>
<dd>Does the path exist? For symbolic links, True if the linked-to file
exists. On some platforms this returns False if Python does not have
permission to stat the file, even if it exists.</dd>
<dt>.isdir()</dt>
<dd>Is the path a directory? Follows symbolic links.</dd>
<dt>.isfile()</dt>
<dd>Is the path a file? Follows symbolic links.</dd>
<dt>.islink()</dt>
<dd>Is the path a symbolic link?</dd>
<dt>.ismount()</dt>
<dd>Is the path a mount point? Returns true if self's parent is on a
different device than self, or if self and its parent are the same
directory.</dd>
<dt>.lexists()</dt>
<dd>Same as <tt class="docutils literal"><span class="pre">.exists()</span></tt> but don't follow a final symbolic link.</dd>
<dt>.lstat()</dt>
<dd>Same as <tt class="docutils literal"><span class="pre">.stat()</span></tt> but do not follow a final symbolic link.</dd>
<dt>.size()</dt>
<dd>Return the file size in bytes.</dd>
<dt>.stat()</dt>
<dd>Return a stat object to test file size, type, permissions, etc.
See <tt class="docutils literal"><span class="pre">os.stat()</span></tt> for details.</dd>
<dt>.statvfs()</dt>
<dd>Return a <tt class="docutils literal"><span class="pre">StatVFS</span></tt> object. This method exists only if the platform
supports it. See <tt class="docutils literal"><span class="pre">os.statvfs()</span></tt> for details.</dd>
</dl>
</div>
<div class="section">
<h2><a class="toc-backref" href="#id20" id="modifying-paths" name="modifying-paths">Modifying paths</a></h2>
<div class="section">
<h3><a class="toc-backref" href="#id21" id="creating-renaming-removing" name="creating-renaming-removing">Creating/renaming/removing</a></h3>
<dl class="docutils">
<dt>.chmod(mode)</dt>
<dd>Change the path's permissions. 'mode' is octal; e.g., 0777.</dd>
<dt>.chown(uid, gid)</dt>
<dd>Change the path's ownership to the numeric uid and gid specified.
Pass -1 if you don't want one of the IDs changed.</dd>
<dt>.mkdir(parents=False)</dt>
<dd>Create the directory, or succeed silently if it already exists. If
'parents' is true, create any necessary ancestor directories.</dd>
<dt>.remove()</dt>
<dd>Delete the file. Raises OSError if it's a directory.</dd>
<dt>.rename(dst, parents=False)</dt>
<dd>Rename self to 'dst' atomically. See <tt class="docutils literal"><span class="pre">os.rename()</span></tt> for additional
details. If 'parents' is True, create any intermediate destination
directories necessary, and delete as many empty leaf source directories as
possible.</dd>
<dt>.rmdir(parents=False)</dt>
<dd>Remove the directory, or succeed silently if it's already gone. If
'parents' is true, also remove as many empty ancestor directories as
possible.</dd>
<dt>.set_times(mtime=None, atime=None)</dt>
<dd>Set the path's modification and access times. If 'mtime' is None, use
the current time. If 'atime' is None or not specified, use the same time
as 'mtime'. To set the times based on another file, see <tt class="docutils literal"><span class="pre">.copy_stat()</span></tt>.</dd>
</dl>
</div>
<div class="section">
<h3><a class="toc-backref" href="#id22" id="symbolic-and-hard-links" name="symbolic-and-hard-links">Symbolic and hard links</a></h3>
<dl class="docutils">
<dt>.hardlink(src)</dt>
<dd>Create a hard link at 'src' pointing to self.</dd>
<dt>.write_link(target)</dt>
<dd>Create a symbolic link at self pointing to 'target'. The link will contain
the exact string value of 'target' without checking whether that path exists
or is a even a valid path for the filesystem.</dd>
<dt>.make_relative_link_to(dst)</dt>
<dd>Make a relative symbolic link from self to dst. Same as
<tt class="docutils literal"><span class="pre">self.write_link(self.rel_path_to(dst))</span></tt>. (New in Unipath 0.2.0.)</dd>
<dt>.read_link()</dt>
<dd>Return the path that this symbolic link points to.</dd>
</dl>
</div>
</div>
<div class="section">
<h2><a class="toc-backref" href="#id23" id="high-level-operations" name="high-level-operations">High-level operations</a></h2>
<dl class="docutils">
<dt>.copy(dst, times=False, perms=False)</dt>
<dd>Copy the file to a destination. 'times' and 'perms' are same as for
<tt class="docutils literal"><span class="pre">.copy_stat()</span></tt>.</dd>
<dt>.copy_stat(dst, times=True, perms=True)</dt>
<dd>Copy the access/modification times and/or the permission bits from this
path to another path.</dd>
<dt>.copy_tree(dst, preserve_symlinks=False, times=False, perms=False)</dt>
<dd>Recursively copy a directory tree to 'dst'. 'dst' must not exist; it will
be created along with any missing ancestors. If 'symlinks' is true,
symbolic links will be recreated with the same path (absolute or relative);
otherwise the links will be followed. 'times' and 'perms' are same as
<tt class="docutils literal"><span class="pre">.copy_stat()</span></tt>. <em>This method is not implemented yet.</em></dd>
<dt>.move(dst)</dt>
<dd>Recursively move a file or directory to another location. This uses
.rename() if possible.</dd>
<dt>.needs_update(other_paths)</dt>
<dd>Return True if self is missing or is older than any other path.
'other_paths' can be a <tt class="docutils literal"><span class="pre">(FS)Path</span></tt>, a string path, or a list/tuple
of these. Recurses through subdirectories but compares only files.</dd>
<dt>.read_file(mode="r")</dt>
<dd>Return the file's content as a <tt class="docutils literal"><span class="pre">str</span></tt> string. This encapsulates the
open/read/close. 'mode' is the same as in Python's <tt class="docutils literal"><span class="pre">open()</span></tt> function.</dd>
<dt>.rmtree(parents=False)</dt>
<dd>Recursively remove this path, no matter whether it's a file or a
directory. Succeed silently if the path doesn't exist. If 'parents' is
true, also try to remove as many empty ancestor directories as possible.</dd>
<dt>.write_file(content, mode="w")</dt>
<dd>Replace the file's content, creating the file if
necessary. 'mode' is the same as in Python's <tt class="docutils literal"><span class="pre">open()</span></tt> function.
'content' is a <tt class="docutils literal"><span class="pre">str</span></tt> string. You'll have to encode Unicode strings
before calling this.</dd>
</dl>
</div>
</div>
<div class="section">
<h1><a class="toc-backref" href="#id24" id="tools" name="tools">Tools</a></h1>
<p>The following functions are in the <tt class="docutils literal"><span class="pre">unipath.tools</span></tt> module.</p>
<div class="section">
<h2><a class="toc-backref" href="#id25" id="dict2dir" name="dict2dir">dict2dir</a></h2>
<p>dict2dir(dir, dic, mode="w") => None</p>
<blockquote>
Create a directory that matches the dict spec. String values are turned
into files named after the key. Dict values are turned into
subdirectories. 'mode' specifies the mode for files. 'dir' can be an
<tt class="docutils literal"><span class="pre">[FS]Path</span></tt> or a string path.</blockquote>
<p>dump_path(path, prefix="", tab=" ", file=None) => None</p>
<blockquote>
<p>Display an ASCII tree of the path. Files are displayed as
"filename (size)". Directories have ":" at the end of the line and
indentation below, like Python syntax blocks. Symbolic links are
shown as "link -> target". 'prefix' is a string prefixed to every
line, normally to controll indentation. 'tab' is the indentation
added for each directory level. 'file' specifies an output file object,
or <tt class="docutils literal"><span class="pre">None</span></tt> for <tt class="docutils literal"><span class="pre">sys.stdout</span></tt>.</p>
<p>A future version of Unipath will have a command-line program to
dump a path.</p>
</blockquote>
</div>
</div>
<div class="section">
<h1><a class="toc-backref" href="#id26" id="non-native-paths" name="non-native-paths">Non-native paths</a></h1>
<p>If you want to make Windows-style paths on Unix or vice-versa, you can
subclass <tt class="docutils literal"><span class="pre">AbstractPath</span></tt> and set the <tt class="docutils literal"><span class="pre">pathlib</span></tt> class attribute to one of
Python's OS-specific path modules (<tt class="docutils literal"><span class="pre">posixpath</span></tt> or <tt class="docutils literal"><span class="pre">ntpath</span></tt>) or a
third-party equivalent. To convert from one syntax to another, pass the path
object to the other constructor.</p>
<p>This is not practical with <tt class="docutils literal"><span class="pre">Path</span></tt> because the OS will reject or misinterpret
non-native paths.</p>
</div>
<div class="section">
<h1><a class="toc-backref" href="#id27" id="history" name="history">History</a></h1>
<dl class="docutils">
<dt>2004-03-07</dt>
<dd><p class="first">Released as path.py by Jason Orendorff <<a class="reference" href="mailto:jason@jorendorff.com">jason@jorendorff.com</a>>.
That version is a subclass of unicode and combines methods from
os.path, os, and shutil, and includes globbing features.
Other contributors are listed in the source.</p>
<ul class="last simple">
<li><a class="reference" href="http://www.jorendorff.com/articles/python/path">http://www.jorendorff.com/articles/python/path</a></li>
</ul>
</dd>
<dt>2005-07</dt>
<dd>Modified by Reinhold Birkenfeld in preparation for a Python PEP.
Convert all filesystem-accessing properties to methods, rename stuff, and
use self.__class__ instead of hardwired constructor to aid subclassing.
Source was in Python CVS in the "sandbox" section but I can't find it in
the current Subversion repository; was it deleted? What's the incantation
to bring it back?</dd>
<dt>2006-01</dt>
<dd><p class="first">Modified by Björn Lindqvist <<a class="reference" href="mailto:bjourne@gmail.com">bjourne@gmail.com</a>> for PEP 355.
Replace .joinpath() with a multi-argument constructor.</p>
<ul class="last simple">
<li>overview: <a class="reference" href="http://www.python.org/dev/peps/pep-0355/">http://www.python.org/dev/peps/pep-0355/</a></li>
<li>code: <a class="reference" href="http://wiki.python.org/moin/PathModule">http://wiki.python.org/moin/PathModule</a></li>
</ul>
</dd>
<dt>2006</dt>
<dd><p class="first">Influenced by Noam Raphael's alternative path module. This subclasses
tuple rather than unicode, representing a tuple of directory components a
la <tt class="docutils literal"><span class="pre">tuple(os.path.splitall("a/b"))</span></tt>. The discussion covers several design
decisions and open issues.</p>
<ul class="last simple">
<li>overview: <a class="reference" href="http://wiki.python.org/moin/AlternativePathClass">http://wiki.python.org/moin/AlternativePathClass</a></li>
<li>code: <a class="reference" href="http://wiki.python.org/moin/AlternativePathModule">http://wiki.python.org/moin/AlternativePathModule</a></li>
<li>discussion: <a class="reference" href="http://wiki.python.org/moin/AlternativePathDiscussion">http://wiki.python.org/moin/AlternativePathDiscussion</a></li>
</ul>
</dd>
<dt>2007-01</dt>
<dd><p class="first">Renamed unipath and modified by Mike Orr <<a class="reference" href="mailto:sluggoster@gmail.com">sluggoster@gmail.com</a>>.
Move filesystem operations into a subclass FSPath. Add and rename methods
and properties. Influenced by these mailing-list threads:</p>
<ul class="last simple">
<li>@@MO coming soon</li>
</ul>
</dd>
<dt>2008-05</dt>
<dd>Released version 0.2.0. Renamed <tt class="docutils literal"><span class="pre">Path</span></tt> to <tt class="docutils literal"><span class="pre">AbstractPath</span></tt>, and
<tt class="docutils literal"><span class="pre">FSPath</span></tt> to <tt class="docutils literal"><span class="pre">Path</span></tt>.</dd>
</dl>
</div>
<div class="section">
<h1><a class="toc-backref" href="#id28" id="comparision-with-os-os-path-shutil-and-path-py" name="comparision-with-os-os-path-shutil-and-path-py">Comparision with os/os.path/shutil and path.py</a></h1>
<pre class="literal-block">
p = any path, f = file, d = directory, l = link
fsp, fsf, fsd, fsl = filesystem path (i.e., ``Path`` only)
- = not implemented
</pre>
<p>Functions are listed in the same order as the Python Library Reference, version
2.5. (Sorry the table is badly formatted.)</p>
<pre class="literal-block">
os/os.path/shutil path.py Unipath Notes
================= ============== ========== =======
os.path.abspath(p) p.abspath() p.absolute() Return absolute path.
os.path.basename(p) p.name p.name
os.path.commonprefix(p) - - Common prefix. [1]_
os.path.dirname(p) p.parent p.parent All except the last component.
os.path.exists(p) p.exists() fsp.exists() Does the path exist?
os.path.lexists(p) p.lexists() fsp.lexists() Does the symbolic link exist?
os.path.expanduser(p) p.expanduser() p.expand_user() Expand "~" and "~user" prefix.
os.path.expandvars(p) p.expandvars() p.expand_vars() Expand "$VAR" environment variables.
os.path.getatime(p) p.atime fsp.atime() Last access time.
os.path.getmtime(p) p.mtime fsp.mtime() Last modify time.
os.path.getctime(p) p.ctime fsp.ctime() Platform-specific "ctime".
os.path.getsize(p) p.size fsp.size() File size.
os.path.isabs(p) p.isabs() p.isabsolute Is path absolute?
os.path.isfile(p) p.isfile() fsp.isfile() Is a file?
os.path.isdir(p) p.isdir() fsp.isdir() Is a directory?
os.path.islink(p) p.islink() fsp.islink() Is a symbolic link?
os.path.ismount(p) p.ismount() fsp.ismount() Is a mount point?
os.path.join(p, "Q/R") p.joinpath("Q/R") [FS]Path(p, "Q/R") Join paths.
-or-
p.child("Q", "R")
os.path.normcase(p) p.normcase() p.norm_case() Normalize case.
os.path.normpath(p) p.normpath() p.norm() Normalize path.
os.path.realpath(p) p.realpath() fsp.real_path() Real path without symbolic links.
os.path.samefile(p, q) p.samefile(q) fsp.same_file(q) True if both paths point to the same filesystem item.
os.path.sameopenfile(d1, d2) - - [Not a path operation.]
os.path.samestat(st1, st2) - - [Not a path operation.]
os.path.split(p) p.splitpath() (p.parent, p.name) Split path at basename.
os.path.splitdrive(p) p.splitdrive() - [2]_
os.path.splitext(p) p.splitext() - [2]_
os.path.splitunc(p) p.splitunc() - [2]_
os.path.walk(p, func, args) - - [3]_
os.access(p, const) p.access(const) - [4]_
os.chdir(d) - fsd.chdir() Change current directory.
os.fchdir(fd) - - [Not a path operation.]
os.getcwd() path.getcwd() FSPath.cwd() Get current directory.
os.chroot(d) d.chroot() - [5]_
os.chmod(p, 0644) p.chmod(0644) fsp.chmod(0644) Change mode (permission bits).
os.chown(p, uid, gid) p.chown(uid, gid) fsp.chown(uid, gid) Change ownership.
os.lchown(p, uid, gid) - - [6]_
os.link(src, dst) p.link(dst) fsp.hardlink(dst) Make hard link.
os.listdir(d) - fsd.listdir(names_only=True) List directory; return base filenames.
os.lstat(p) p.lstat() fsp.lstat() Like stat but don't follow symbolic link.
os.mkfifo(p, 0666) - - [Not enough of a path operation.]
os.mknod(p, ...) - - [Not enough of a path operation.]
os.major(device) - - [Not a path operation.]
os.minor(device) - - [Not a path operation.]
os.makedev(...) - - [Not a path operation.]
os.mkdir(d, 0777) d.mkdir(0777) fsd.mkdir(mode=0777) Create directory.
os.makedirs(d, 0777) d.makedirs(0777) fsd.mkdir(True, 0777) Create a directory and necessary parent directories.
os.pathconf(p, name) p.pathconf(name) - Return Posix path attribute. (What the hell is this?)
os.readlink(l) l.readlink() fsl.read_link() Return the path a symbolic link points to.
os.remove(f) f.remove() fsf.remove() Delete file.
os.removedirs(d) d.removedirs() fsd.rmdir(True) Remove empty directory and all its empty ancestors.
os.rename(src, dst) p.rename(dst) fsp.rename(dst) Rename a file or directory atomically (must be on same device).
os.renames(src, dst) p.renames(dst) fsp.rename(dst, True) Combines os.rename, os.makedirs, and os.removedirs.
os.rmdir(d) d.rmdir() fsd.rmdir() Delete empty directory.
os.stat(p) p.stat() fsp.stat() Return a "stat" object.
os.statvfs(p) p.statvfs() fsp.statvfs() Return a "statvfs" object.
os.symlink(src, dst) p.symlink(dst) fsp.write_link(link_text) Create a symbolic link.
("write_link" argument order is opposite from Python's!)
os.tempnam(...) - - [7]_
os.unlink(f) f.unlink() - Same as .remove().
os.utime(p, times) p.utime(times) fsp.set_times(mtime, atime) Set access/modification times.
os.walk(...) - - [3]_
shutil.copyfile(src, dst) f.copyfile(dst) fsf.copy(dst, ...) Copy file. Unipath method is more than copyfile but less than copy2.
shutil.copyfileobj(...) - - [Not a path operation.]
shutil.copymode(src, dst) p.copymode(dst) fsp.copy_stat(dst, ...) Copy permission bits only.
shutil.copystat(src, dst) p.copystat(dst) fsp.copy_stat(dst, ...) Copy stat bits.
shutil.copy(src, dst) f.copy(dst) - High-level copy a la Unix "cp".
shutil.copy2(src, dst) f.copy2(dst) - High-level copy a la Unix "cp -p".
shutil.copytree(...) d.copytree(...) fsp.copy_tree(...) Copy directory tree. (Not implemented in Unipath 0.1.0.)
shutil.rmtree(...) d.rmtree(...) fsp.rmtree(...) Recursively delete directory tree. (Unipath has enhancements.)
shutil.move(src, dst) p.move(dst) fsp.move(dst) Recursively move a file or directory, using os.rename() if possible.
A + B A + B A+B Concatenate paths.
os.path.join(A, B) A / B [FS]Path(A, B) Join paths.
-or-
p.child(B)
- p.expand() p.expand() Combines expanduser, expandvars, normpath.
os.path.dirname(p) p.parent p.parent Path without final component.
os.path.basename(p) p.name p.name Final component only.
[8]_ p.namebase p.stem Final component without extension.
[9]_ p.ext p.ext Extension only.
os.path.splitdrive(p)[0] p.drive - [2]_
- p.stripext() - Strip final extension.
- p.uncshare - [2]_
- p.splitall() p.components() List of path components. (Unipath has special first element.)
- p.relpath() fsp.relative() Relative path to current directory.
- p.relpathto(dst) fsp.rel_path_to(dst) Relative path to 'dst'.
- d.listdir() fsd.listdir() List directory, return paths.
- d.files() fsd.listdir(filter=FILES) List files in directory, return paths.
- d.dirs() fsd.listdir(filter=DIRS) List subdirectories, return paths.
- d.walk(...) fsd.walk(...) Recursively yield files and directories.
- d.walkfiles(...) fsd.walk(filter=FILES) Recursively yield files.
- d.walkdirs(...) fsd.walk(filter=DIRS) Recursively yield directories.
- p.fnmatch(pattern) - True if self.name matches glob pattern.
- p.glob(pattern) - Advanced globbing.
- f.open(mode) - Return open file object.
- f.bytes() fsf.read_file("rb") Return file contents in binary mode.
- f.write_bytes() fsf.write_file(content, "wb") Replace file contents in binary mode.
- f.text(...) fsf.read_file() Return file content. (Encoding args not implemented yet.)
- f.write_text(...) fsf.write_file(content) Replace file content. (Not all Orendorff args supported.)
- f.lines(...) - Return list of lines in file.
- f.write_lines(...) - Write list of lines to file.
- f.read_md5() - Calculate MD5 hash of file.
- p.owner - Advanded "get owner" operation.
- p.readlinkabs() - Return the path this symlink points to, converting to absolute path.
- p.startfile() - What the hell is this?
- - p.split_root() Unified "split root" method.
- - p.ancestor(N) Same as specifying .parent N times.
- - p.child(...) "Safe" way to join paths.
- - fsp.needs_update(...) True if self is missing or older than any of the other paths.
</pre>
<table class="docutils footnote" frame="void" id="id1" rules="none">
<colgroup><col class="label" /><col /></colgroup>
<tbody valign="top">
<tr><td class="label"><a name="id1">[1]</a></td><td>The Python method is too dumb; it can end a prefix in the middle of a</td></tr>
</tbody>
</table>
<table class="docutils footnote" frame="void" id="id2" rules="none">
<colgroup><col class="label" /><col /></colgroup>
<tbody valign="top">
<tr><td class="label"><a name="id2">[2]</a></td><td>Closest equivalent is <tt class="docutils literal"><span class="pre">p.split_root()</span></tt> for approximate equivalent.</td></tr>
</tbody>
</table>
<table class="docutils footnote" frame="void" id="id3" rules="none">
<colgroup><col class="label" /><col /></colgroup>
<tbody valign="top">
<tr><td class="label"><a name="id3">[3]</a></td><td>More convenient alternatives exist.</td></tr>
</tbody>
</table>
<table class="docutils footnote" frame="void" id="id4" rules="none">
<colgroup><col class="label" /><col /></colgroup>
<tbody valign="top">
<tr><td class="label"><a name="id4">[4]</a></td><td>Inconvenient constants; not used enough to port.</td></tr>
</tbody>
</table>
<table class="docutils footnote" frame="void" id="id5" rules="none">
<colgroup><col class="label" /><col /></colgroup>
<tbody valign="top">
<tr><td class="label"><a name="id5">[5]</a></td><td>Chroot is more of an OS operation than a path operation. Plus it's
dangerous.</td></tr>
</tbody>
</table>
<table class="docutils footnote" frame="void" id="id6" rules="none">
<colgroup><col class="label" /><col /></colgroup>
<tbody valign="top">
<tr><td class="label"><a name="id6">[6]</a></td><td>Ownership of symbolic link doesn't matter because the OS never
consults its permission bits.</td></tr>
</tbody>
</table>
<!-- [7]_ ``os.tempnam`` is insecure; use ``os.tmpfile`` or ``tempfile`` module
instead. -->
<!-- [8]_ ``os.path.splitext(os.path.split(p))[0]`` -->
<!-- [9]_ ``os.path.splitext(os.path.split(p))[1]`` -->
<!-- [10]_ Closest equivalent is ``p.split_root()[0]``. -->
</div>
<div class="section">
<h1><a class="toc-backref" href="#id29" id="design-decisions-open-issues" name="design-decisions-open-issues">Design decisions / open issues</a></h1>
<p>(Sorry this is so badly organized.)</p>
<p>The original impetus for Unipath was to get object-oriented paths into the
Python standard library. All the previous path classes were rejected as
too large and monolithic, especially for mixing pathname manipulations and
filesystem methods in the same class. Upon reflection, it's mainly the
pathname operations that need to be OO-ified because they are often nested in
expressions. There's a small difference between <tt class="docutils literal"><span class="pre">p.mkdir()</span></tt> and
<tt class="docutils literal"><span class="pre">os.mkdir(p)</span></tt>, but there's a huge difference between
<tt class="docutils literal"><span class="pre">os.path.join(os.path.dirname(os.path.dirname("/A/B/C"))),</span> <span class="pre">"app2/lib")</span></tt> and
<tt class="docutils literal"><span class="pre">Path("/A/B/C").parent.parent.child("app2",</span> <span class="pre">"lib")</span></tt>: the former is flat-out
unreadable. So I have kept <tt class="docutils literal"><span class="pre">Path</span></tt> to a conservative API that hopefully most
Pythoneers can agree on. I allowed myself more freedom with <tt class="docutils literal"><span class="pre">FSPath</span></tt>
because it's unclear that a class with filesystem methods would ever be
accepted into the stdlib anyway, and I needed an API I'd want to use in my own
programs. (<tt class="docutils literal"><span class="pre">Path</span></tt> was renamed to <tt class="docutils literal"><span class="pre">AbstractPath</span></tt> in Unipath 0.2.0, and
<tt class="docutils literal"><span class="pre">FSPath</span></tt> to <tt class="docutils literal"><span class="pre">Path</span></tt>. This section uses the older vocabulary.)</p>
<p>Another important point is that properties may not access the filesystem.
Only methods may access the filesystem. So <tt class="docutils literal"><span class="pre">p.parent</span></tt> is a property, but
<tt class="docutils literal"><span class="pre">p.mtime()</span></tt> is a method. This required turning some of Orendorff's
properties into methods.</p>
<p>The actual <tt class="docutils literal"><span class="pre">FSPath</span></tt> class ended up closer to Orendorff's original than
I had intended, because several of the planned innovations (from python-3000
suggestions, Raphael's alternative path class, and my own mind) turned to be
not necessarily superior in actual programs, whereas Orendorff's methods have
proven themselves reliable in production systems for three years now, so I
deferred to them when in doubt.</p>
<p>The biggest such move was making <tt class="docutils literal"><span class="pre">FSPath</span></tt> a
subclass of <tt class="docutils literal"><span class="pre">Path</span></tt>. Originally I had tried to make them unrelated classes
(<tt class="docutils literal"><span class="pre">FSPath</span></tt> containing a <tt class="docutils literal"><span class="pre">Path</span></tt>), but this became unworkable in the
implementation due to the constant need to call both types of methods.
(Say you have an FSPath directory and you need to join a
filename to it and then delete the file; do you really want to convert from
FSPath to Path and back again? Do you <em>really</em> want to write
"FSPath(Path(my_fspath.path, 'foo'))"?) So one class is better than two, even
if the BDFL disapproves. I opted for the best of both worlds via inheritance,
so those who want one class can pretend it is, and those who want two classes
can get a warm fuzzy feeling that they're defined separately. (They can even
ignore <tt class="docutils literal"><span class="pre">FSPath</span></tt> and use <tt class="docutils literal"><span class="pre">Path</span></tt> with <tt class="docutils literal"><span class="pre">os.*</span></tt> functions if they prefer.)
If <tt class="docutils literal"><span class="pre">Path</span></tt> is someday accepted into the standard libary, <tt class="docutils literal"><span class="pre">FSPath</span></tt> will
become a subclass of that. And others can subclass <tt class="docutils literal"><span class="pre">FSPath</span></tt> or write an
alternative if they don't like my API.</p>
<p>I also intended to put all non-trivial code into generic functions that
third-party path libraries could call. But that also became unworkable due to
the tight integration that naturally occurs between the methods, one calling
another. What's really needed now is for <tt class="docutils literal"><span class="pre">FSPath</span></tt> to get into the real world
so we can see which generic code actually is valuable, and then those can be
factored out later.</p>
<p><tt class="docutils literal"><span class="pre">.stem</span></tt> is called stem because "namebase" can be confused with
<tt class="docutils literal"><span class="pre">os.path.basename()</span></tt>, "name_without_ext" is too wordy, and "name_no_ext" is
looks like bad English.</p>
<p>All method names have underscores between words except those starting with
"is", "mk", "rm", and "stat". The "is" methods are so highly used that
deviating from the <tt class="docutils literal"><span class="pre">os.path</span></tt>/Orendorff spelling would trip up a lot of
programmers, including me. "mk" and "rm" I just like. (Be glad I didn't
rename <tt class="docutils literal"><span class="pre">.copy_tree</span></tt> to "cptree" to match <tt class="docutils literal"><span class="pre">.rmtree</span></tt>.) (or ".drive" and
".unc" properties) are not needed. They may be added if they prove necessary,
but then how do you get "everything except the drive" or "everything except the
UNC prefix". I also had to move the slash following the UNC prefix to the
prefix itself, to maintain the rule that everything after the first component
is a relative path.</p>
<p>I tried making a smart stat object so that one could do "p.stat().size" and
"p.stat().isdir". This was one of the proposals for Raphael's class, to get
rid of a bunch of top-level methods and obviate the need for a set of "l"
methods covering the "stat" and "lstat" operations. I also made a phony stat
object if the path didn't exist, to hang the ".exists" attribute off. But I
was so used to typing <tt class="docutils literal"><span class="pre">p.isdir()</span></tt> etc from Orendorff that I couldn't adjust.
And Python has only one "l" function anyway, <tt class="docutils literal"><span class="pre">os.path.lexists()</span></tt>. <em>And</em> I
didn't want to write the stat object in C, meaning every stat would incur
Python overhead to convert the result attributes. So in the end I decided to
keep the methods shadowing the <tt class="docutils literal"><span class="pre">os.path</span></tt> convenience functions, remove the
"get" prefix from the "get" methods ("getmtime"), and let <tt class="docutils literal"><span class="pre">.stat</span></tt> and
<tt class="docutils literal"><span class="pre">.statvfs</span></tt> return the Python default object. I'm still tempted to make
<tt class="docutils literal"><span class="pre">.stat()</span></tt> and <tt class="docutils literal"><span class="pre">.statvfs</span></tt> return <tt class="docutils literal"><span class="pre">None</span></tt> if the path doesn't exist (rather
than raising <tt class="docutils literal"><span class="pre">OSError</span></tt>), but I'm not sure that's necessarily <em>better</em> so I
held off on that. Presumably one wouldn't use <tt class="docutils literal"><span class="pre">.stat()</span></tt> that much anyway
since the other methods are more convenient.</p>
<p><tt class="docutils literal"><span class="pre">.components()</span></tt> comes from Raphael's class, the concept of treating paths as
a list of components, with the first component being the filesystem root (for
an absolute path). This required unifying Posix and Windows roots into a
common definition. <tt class="docutils literal"><span class="pre">.split_root()</span></tt> handles drive paths and UNC paths, so
"splitdrive" and "splitunc" (or ".drive" and ".unc" properties) were deemed
unnecessary. They may be added later if needed. One problem with ".drive" and
".unc" properties is how to specify "everything except the drive" and
"everything except the UNC prefix", which are needed to recreate the path or
derive a similar path. The slash after the UNC prefix was also moved to the
prefix, to maintain the rule that all components after the first make a
relative path.</p>
<p>"Components" turned out to be a useful way to convert paths from one platform
to another, which was one of Talin's requests. However, what Talin really
wanted was to put Posix paths in a config file and have them translate to the
native platform. Since <tt class="docutils literal"><span class="pre">.norm()</span></tt> and <tt class="docutils literal"><span class="pre">.norm_case()</span></tt> already do this on
Windows, it's questionable how much cross-platform support is really necessary.
Especially since <tt class="docutils literal"><span class="pre">macpath</span></tt> is obsolete now that Mac OS X uses Posix, and Mac
OS 9 is about to be dropped from Python. So the multi-platform code is
probational.</p>
<p>Joining paths is done via the constructor, which takes multiple positional
arguments. This was deemed as better than Orendorff's ".joinpath" method for
reasons I'm not sure of.</p>
<p><tt class="docutils literal"><span class="pre">.child()</span></tt> was requested by Glyph, to create safe subpaths that can never
reach outside their parent directory even if based on untrusted user strings.
It's also sneaky way to do "joinpath" when you're really prefer to use a method
rather than the costructor, as long as each component has to be passed as a
separate argument.</p>
<p>Orendorff has ".listdir", ".dirs", and ".files" methods (non-recursive), and
".walk", ".walkdirs", and "walkfiles" (recursive). Raphael has one ".glob"
method to rule them all. I went back and forth on this several times and
finally settled on <tt class="docutils literal"><span class="pre">.listdir</span></tt> (non-recursive) and <tt class="docutils literal"><span class="pre">.walk</span></tt> (recursive), with
a 'filter' argument to return only files or directories. Neither Orendorff nor
Raphael nor <tt class="docutils literal"><span class="pre">os.walk</span></tt> handle symlinks adequately in my opinion: sometimes you
want to exclude symlinks and then list them separately. <tt class="docutils literal"><span class="pre">.listdir</span></tt> has a
'names_only' option to make it return just the filenames like <tt class="docutils literal"><span class="pre">os.listdir</span></tt>,
because sometimes that's what you need, and there's no reason to create paths
you're just going to unpack again anyway. <tt class="docutils literal"><span class="pre">.listdir</span></tt> and <tt class="docutils literal"><span class="pre">.walk</span></tt> are
separate methods because implementing them as one is complicated -- they have
so many contingencies. <tt class="docutils literal"><span class="pre">.listdir()</span></tt> and <tt class="docutils literal"><span class="pre">.listdir(names_only=True)</span></tt> are
the same method because I couldn't come up with a better name for the former.
I dropped the name "glob" because it's meaningless to non-Unix users.</p>
<p><tt class="docutils literal"><span class="pre">.absolute</span></tt>, <tt class="docutils literal"><span class="pre">.relative</span></tt>, and <tt class="docutils literal"><span class="pre">.resolve</span></tt> are hopefully better named than
Orendorff's "abspath", "relpath", and "realpath", which were taken directly
from <tt class="docutils literal"><span class="pre">os.path</span></tt>. <tt class="docutils literal"><span class="pre">.hardlink</span></tt> is so-named because it's less used than
<tt class="docutils literal"><span class="pre">.symlink</span></tt> nowadays, and a method named ".link" is easy to misinterpret.</p>
<p>I wanted a symbolic syntax for <tt class="docutils literal"><span class="pre">.chmod</span></tt> ("u=rwx,g+w") and a companion
function to parse a numeric mode, and user names/group names for <tt class="docutils literal"><span class="pre">.chown</span></tt>,
but those were deferred to get the basic classes out the door. The methods
take the same arguments as their <tt class="docutils literal"><span class="pre">os</span></tt> counterparts.</p>
</div>
</div>
</body>
</html>
|
