1ZDIR(3)                           CZMQ Manual                          ZDIR(3)
2
3
4

NAME

6       zdir - work with file-system directories
7

SYNOPSIS

9       //  This is a stable class, and may not change except for emergencies. It
10       //  is provided in stable builds.
11       //  Create a new directory item that loads in the full tree of the specified
12       //  path, optionally located under some parent path. If parent is "-", then
13       //  loads only the top-level directory, and does not use parent as a path.
14       CZMQ_EXPORT zdir_t *
15           zdir_new (const char *path, const char *parent);
16
17       //  Destroy a directory tree and all children it contains.
18       CZMQ_EXPORT void
19           zdir_destroy (zdir_t **self_p);
20
21       //  Return directory path
22       CZMQ_EXPORT const char *
23           zdir_path (zdir_t *self);
24
25       //  Return last modification time for directory.
26       CZMQ_EXPORT time_t
27           zdir_modified (zdir_t *self);
28
29       //  Return total hierarchy size, in bytes of data contained in all files
30       //  in the directory tree.
31       CZMQ_EXPORT off_t
32           zdir_cursize (zdir_t *self);
33
34       //  Return directory count
35       CZMQ_EXPORT size_t
36           zdir_count (zdir_t *self);
37
38       //  Returns a sorted list of zfile objects; Each entry in the list is a pointer
39       //  to a zfile_t item already allocated in the zdir tree. Do not destroy the
40       //  original zdir tree until you are done with this list.
41       //  Caller owns return value and must destroy it when done.
42       CZMQ_EXPORT zlist_t *
43           zdir_list (zdir_t *self);
44
45       //  Remove directory, optionally including all files that it contains, at
46       //  all levels. If force is false, will only remove the directory if empty.
47       //  If force is true, will remove all files and all subdirectories.
48       CZMQ_EXPORT void
49           zdir_remove (zdir_t *self, bool force);
50
51       //  Calculate differences between two versions of a directory tree.
52       //  Returns a list of zdir_patch_t patches. Either older or newer may
53       //  be null, indicating the directory is empty/absent. If alias is set,
54       //  generates virtual filename (minus path, plus alias).
55       //  Caller owns return value and must destroy it when done.
56       CZMQ_EXPORT zlist_t *
57           zdir_diff (zdir_t *older, zdir_t *newer, const char *alias);
58
59       //  Return full contents of directory as a zdir_patch list.
60       //  Caller owns return value and must destroy it when done.
61       CZMQ_EXPORT zlist_t *
62           zdir_resync (zdir_t *self, const char *alias);
63
64       //  Load directory cache; returns a hash table containing the SHA-1 digests
65       //  of every file in the tree. The cache is saved between runs in .cache.
66       //  Caller owns return value and must destroy it when done.
67       CZMQ_EXPORT zhash_t *
68           zdir_cache (zdir_t *self);
69
70       //  Print contents of directory to open stream
71       CZMQ_EXPORT void
72           zdir_fprint (zdir_t *self, FILE *file, int indent);
73
74       //  Print contents of directory to stdout
75       CZMQ_EXPORT void
76           zdir_print (zdir_t *self, int indent);
77
78       //  Create a new zdir_watch actor instance:
79       //
80       //      zactor_t *watch = zactor_new (zdir_watch, NULL);
81       //
82       //  Destroy zdir_watch instance:
83       //
84       //      zactor_destroy (&watch);
85       //
86       //  Enable verbose logging of commands and activity:
87       //
88       //      zstr_send (watch, "VERBOSE");
89       //
90       //  Subscribe to changes to a directory path:
91       //
92       //      zsock_send (watch, "ss", "SUBSCRIBE", "directory_path");
93       //
94       //  Unsubscribe from changes to a directory path:
95       //
96       //      zsock_send (watch, "ss", "UNSUBSCRIBE", "directory_path");
97       //
98       //  Receive directory changes:
99       //      zsock_recv (watch, "sp", &path, &patches);
100       //
101       //      // Delete the received data.
102       //      free (path);
103       //      zlist_destroy (&patches);
104       CZMQ_EXPORT void
105           zdir_watch (zsock_t *pipe, void *unused);
106
107       //  Self test of this class.
108       CZMQ_EXPORT void
109           zdir_test (bool verbose);
110
111       Please add '@interface' section in './../src/zdir.c'.
112

DESCRIPTION

114       The zdir class gives access to the file system index. It will load a
115       directory tree (a directory plus all child directories) into a zdir
116       structure and then let you navigate that structure. It exists mainly to
117       wrap non-portable OS functions to do this.
118
119       Please add @discuss section in ./../src/zdir.c.
120

EXAMPLE

122       From zdir_test method.
123
124           // need to create a file in the test directory we're watching
125           // in order to ensure the directory exists
126           zfile_t *initfile = zfile_new ("./zdir-test-dir", "initial_file");
127           assert (initfile);
128           zfile_output (initfile);
129           fprintf (zfile_handle (initfile), "initial file\n");
130           zfile_close (initfile);
131           zfile_destroy (&initfile);
132
133           zdir_t *older = zdir_new ("zdir-test-dir", NULL);
134           assert (older);
135           if (verbose) {
136               printf ("\n");
137               zdir_dump (older, 0);
138           }
139           zdir_t *newer = zdir_new (".", NULL);
140           assert (newer);
141           zlist_t *patches = zdir_diff (older, newer, "/");
142           assert (patches);
143           while (zlist_size (patches)) {
144               zdir_patch_t *patch = (zdir_patch_t *) zlist_pop (patches);
145               zdir_patch_destroy (&patch);
146           }
147           zlist_destroy (&patches);
148           zdir_destroy (&older);
149           zdir_destroy (&newer);
150
151           zdir_t *nosuch = zdir_new ("does-not-exist", NULL);
152           assert (nosuch == NULL);
153
154           // zdir_watch test:
155           zactor_t *watch = zactor_new (zdir_watch, NULL);
156           assert (watch);
157
158           if (verbose) {
159               zsock_send (watch, "s", "VERBOSE");
160               assert (zsock_wait (watch) == 0);
161           }
162
163           zclock_sleep (1001); // wait for initial file to become 'stable'
164
165           zsock_send (watch, "si", "TIMEOUT", 100);
166           assert (zsock_wait (watch) == 0);
167
168           zsock_send (watch, "ss", "SUBSCRIBE", "zdir-test-dir");
169           assert (zsock_wait (watch) == 0);
170
171           zsock_send (watch, "ss", "UNSUBSCRIBE", "zdir-test-dir");
172           assert (zsock_wait (watch) == 0);
173
174           zsock_send (watch, "ss", "SUBSCRIBE", "zdir-test-dir");
175           assert (zsock_wait (watch) == 0);
176
177           zfile_t *newfile = zfile_new ("zdir-test-dir", "test_abc");
178           zfile_output (newfile);
179           fprintf (zfile_handle (newfile), "test file\n");
180           zfile_close (newfile);
181
182           zpoller_t *watch_poll = zpoller_new (watch, NULL);
183
184           // poll for a certain timeout before giving up and failing the test.
185           assert (zpoller_wait (watch_poll, 1001) == watch);
186
187           // wait for notification of the file being added
188           char *path;
189           int rc = zsock_recv (watch, "sp", &path, &patches);
190           assert (rc == 0);
191
192           assert (streq (path, "zdir-test-dir"));
193           free (path);
194
195           assert (zlist_size (patches) == 1);
196
197           zdir_patch_t *patch = (zdir_patch_t *) zlist_pop (patches);
198           assert (streq (zdir_patch_path (patch), "zdir-test-dir"));
199
200           zfile_t *patch_file = zdir_patch_file (patch);
201           assert (streq (zfile_filename (patch_file, ""), "zdir-test-dir/test_abc"));
202
203           zdir_patch_destroy (&patch);
204           zlist_destroy (&patches);
205
206           // remove the file
207           zfile_remove (newfile);
208           zfile_destroy (&newfile);
209
210           // poll for a certain timeout before giving up and failing the test.
211           assert (zpoller_wait (watch_poll, 1001) == watch);
212
213           // wait for notification of the file being removed
214           rc = zsock_recv (watch, "sp", &path, &patches);
215           assert (rc == 0);
216
217           assert (streq (path, "zdir-test-dir"));
218           free (path);
219
220           assert (zlist_size (patches) == 1);
221
222           patch = (zdir_patch_t *) zlist_pop (patches);
223           assert (streq (zdir_patch_path (patch), "zdir-test-dir"));
224
225           patch_file = zdir_patch_file (patch);
226           assert (streq (zfile_filename (patch_file, ""), "zdir-test-dir/test_abc"));
227
228           zdir_patch_destroy (&patch);
229           zlist_destroy (&patches);
230
231           zpoller_destroy (&watch_poll);
232           zactor_destroy (&watch);
233
234           // clean up by removing the test directory.
235           zdir_t *testdir = zdir_new ("zdir-test-dir", NULL);
236           zdir_remove (testdir, true);
237           zdir_destroy (&testdir);
238
239

AUTHORS

241       The czmq manual was written by the authors in the AUTHORS file.
242

RESOURCES

244       Main web site:
245
246       Report bugs to the email <zeromq-dev@lists.zeromq.org[1]>
247
249       Copyright (c) the Contributors as noted in the AUTHORS file. This file
250       is part of CZMQ, the high-level C binding for 0MQ:
251       http://czmq.zeromq.org. This Source Code Form is subject to the terms
252       of the Mozilla Public License, v. 2.0. If a copy of the MPL was not
253       distributed with this file, You can obtain one at
254       http://mozilla.org/MPL/2.0/. LICENSE included with the czmq
255       distribution.
256

NOTES

258        1. zeromq-dev@lists.zeromq.org
259           mailto:zeromq-dev@lists.zeromq.org
260
261
262
263CZMQ 4.0.2                        12/31/2016                           ZDIR(3)
Impressum