Provided by: libczmq-dev_4.2.1-1_amd64 bug

NAME

       zdir - Class for work with file-system directories

SYNOPSIS

       //  This is a stable class, and may not change except for emergencies. It
       //  is provided in stable builds.
       //  Create a new directory item that loads in the full tree of the specified
       //  path, optionally located under some parent path. If parent is "-", then
       //  loads only the top-level directory, and does not use parent as a path.
       CZMQ_EXPORT zdir_t *
           zdir_new (const char *path, const char *parent);

       //  Destroy a directory tree and all children it contains.
       CZMQ_EXPORT void
           zdir_destroy (zdir_t **self_p);

       //  Return directory path
       CZMQ_EXPORT const char *
           zdir_path (zdir_t *self);

       //  Return last modification time for directory.
       CZMQ_EXPORT time_t
           zdir_modified (zdir_t *self);

       //  Return total hierarchy size, in bytes of data contained in all files
       //  in the directory tree.
       CZMQ_EXPORT off_t
           zdir_cursize (zdir_t *self);

       //  Return directory count
       CZMQ_EXPORT size_t
           zdir_count (zdir_t *self);

       //  Returns a sorted list of zfile objects; Each entry in the list is a pointer
       //  to a zfile_t item already allocated in the zdir tree. Do not destroy the
       //  original zdir tree until you are done with this list.
       //  Caller owns return value and must destroy it when done.
       CZMQ_EXPORT zlist_t *
           zdir_list (zdir_t *self);

       //  Remove directory, optionally including all files that it contains, at
       //  all levels. If force is false, will only remove the directory if empty.
       //  If force is true, will remove all files and all subdirectories.
       CZMQ_EXPORT void
           zdir_remove (zdir_t *self, bool force);

       //  Calculate differences between two versions of a directory tree.
       //  Returns a list of zdir_patch_t patches. Either older or newer may
       //  be null, indicating the directory is empty/absent. If alias is set,
       //  generates virtual filename (minus path, plus alias).
       //  Caller owns return value and must destroy it when done.
       CZMQ_EXPORT zlist_t *
           zdir_diff (zdir_t *older, zdir_t *newer, const char *alias);

       //  Return full contents of directory as a zdir_patch list.
       //  Caller owns return value and must destroy it when done.
       CZMQ_EXPORT zlist_t *
           zdir_resync (zdir_t *self, const char *alias);

       //  Load directory cache; returns a hash table containing the SHA-1 digests
       //  of every file in the tree. The cache is saved between runs in .cache.
       //  Caller owns return value and must destroy it when done.
       CZMQ_EXPORT zhash_t *
           zdir_cache (zdir_t *self);

       //  Print contents of directory to open stream
       CZMQ_EXPORT void
           zdir_fprint (zdir_t *self, FILE *file, int indent);

       //  Print contents of directory to stdout
       CZMQ_EXPORT void
           zdir_print (zdir_t *self, int indent);

       //  Create a new zdir_watch actor instance:
       //
       //      zactor_t *watch = zactor_new (zdir_watch, NULL);
       //
       //  Destroy zdir_watch instance:
       //
       //      zactor_destroy (&watch);
       //
       //  Enable verbose logging of commands and activity:
       //
       //      zstr_send (watch, "VERBOSE");
       //
       //  Subscribe to changes to a directory path:
       //
       //      zsock_send (watch, "ss", "SUBSCRIBE", "directory_path");
       //
       //  Unsubscribe from changes to a directory path:
       //
       //      zsock_send (watch, "ss", "UNSUBSCRIBE", "directory_path");
       //
       //  Receive directory changes:
       //      zsock_recv (watch, "sp", &path, &patches);
       //
       //      // Delete the received data.
       //      free (path);
       //      zlist_destroy (&patches);
       CZMQ_EXPORT void
           zdir_watch (zsock_t *pipe, void *unused);

       //  Self test of this class.
       CZMQ_EXPORT void
           zdir_test (bool verbose);

       Please add '@interface' section in './../src/zdir.c'.

DESCRIPTION

       The zdir class gives access to the file system index. It will load a directory tree (a
       directory plus all child directories) into a zdir structure and then let you navigate that
       structure. It exists mainly to wrap non-portable OS functions to do this.

       Please add @discuss section in ./../src/zdir.c.

EXAMPLE

       From zdir_test method.

           const char *SELFTEST_DIR_RW = "src/selftest-rw";

           const char *testbasedir  = "zdir-test-dir";
           const char *testfile1 = "initial_file";
           const char *testfile2 = "test_abc";
           char *basedirpath = NULL;   // subdir in a test, under SELFTEST_DIR_RW
           char *filepath1 = NULL;      // pathname to testfile in a test, in dirpath
           char *filepath2 = NULL;      // pathname to testfile in a test, in dirpath

           basedirpath = zsys_sprintf ("%s/%s", SELFTEST_DIR_RW, testbasedir);
           assert (basedirpath);
           filepath1 = zsys_sprintf ("%s/%s", basedirpath, testfile1);
           assert (filepath1);
           filepath2 = zsys_sprintf ("%s/%s", basedirpath, testfile2);
           assert (filepath2);

           /*
           char *relfilepath2 = NULL;      // pathname to testfile in a test, in dirpath
           relfilepath2 = zsys_sprintf ("%s/%s", testbasedir, testfile2);
           assert (relfilepath2);
           */

           // Make sure old aborted tests do not hinder us
           zdir_t *dir = zdir_new (basedirpath, NULL);
           if (dir) {
               zdir_remove (dir, true);
               zdir_destroy (&dir);
           }
           zsys_file_delete (filepath1);
           zsys_file_delete (filepath2);
           zsys_dir_delete  (basedirpath);

           dir = zdir_new ("does-not-exist", NULL);
           if (dir) {
               zdir_remove (dir, true);
               zdir_destroy (&dir);
           }

           // need to create a file in the test directory we're watching
           // in order to ensure the directory exists
           zfile_t *initfile = zfile_new (basedirpath, testfile1);
           assert (initfile);
           zfile_output (initfile);
           fprintf (zfile_handle (initfile), "initial file\n");
           zfile_close (initfile);
           zfile_destroy (&initfile);

           zdir_t *older = zdir_new (basedirpath, NULL);
           assert (older);
           if (verbose) {
               printf ("\n");
               zdir_dump (older, 0);
           }
           zdir_t *newer = zdir_new (SELFTEST_DIR_RW, NULL);
           assert (newer);
           zlist_t *patches = zdir_diff (older, newer, "/");
           assert (patches);
           while (zlist_size (patches)) {
               zdir_patch_t *patch = (zdir_patch_t *) zlist_pop (patches);
               zdir_patch_destroy (&patch);
           }
           zlist_destroy (&patches);
           zdir_destroy (&older);
           zdir_destroy (&newer);

           zdir_t *nosuch = zdir_new ("does-not-exist", NULL);
           assert (nosuch == NULL);

           // zdir_watch test:
           zactor_t *watch = zactor_new (zdir_watch, NULL);
           assert (watch);

           int synced;
           if (verbose) {
               zsock_send (watch, "s", "VERBOSE");
               synced = zsock_wait(watch);
               assert ( synced == 0);
           }

           // wait for initial file to become 'stable'
           #ifdef CZMQ_BUILD_DRAFT_API
           zclock_sleep ((int)zsys_file_stable_age_msec() + 50);
           #else
           zclock_sleep (5050);
           #endif

           zsock_send (watch, "si", "TIMEOUT", 100);
           synced = zsock_wait(watch);
           assert (synced == 0);

           zsock_send (watch, "ss", "SUBSCRIBE", basedirpath);
           synced = zsock_wait(watch);
           assert(synced == 0);

           zsock_send (watch, "ss", "UNSUBSCRIBE", basedirpath);
           synced = zsock_wait(watch);
           assert(synced == 0);

           zsock_send (watch, "ss", "SUBSCRIBE", basedirpath);
           synced = zsock_wait(watch);
           assert(synced == 0);

           zfile_t *newfile = zfile_new (basedirpath, testfile2);
           zfile_output (newfile);
           fprintf (zfile_handle (newfile), "test file\n");
           zfile_close (newfile);

           zpoller_t *watch_poll = zpoller_new (watch, NULL);

           // poll for a certain timeout before giving up and failing the test
           void* polled = NULL;
           #ifdef CZMQ_BUILD_DRAFT_API
           polled = zpoller_wait(watch_poll, (int)zsys_file_stable_age_msec() + 150);
           #else
           polled = zpoller_wait(watch_poll, 5150);
           #endif
           assert (polled == watch);

           // wait for notification of the file being added
           char *path;
           int rc = zsock_recv (watch, "sp", &path, &patches);
           assert (rc == 0);

           assert (streq (path, basedirpath));
           freen (path);

           if (verbose)
               zsys_debug("zdir_test() : added : zlist_size (patches)=%d",
                   zlist_size (patches) );
           assert (zlist_size (patches) == 1);

           zdir_patch_t *patch = (zdir_patch_t *) zlist_pop (patches);
           if (verbose)
               zsys_debug("zdir_test() : added : zdir_patch_path (patch)='%s'",
                   zdir_patch_path (patch) );
           assert (streq (zdir_patch_path (patch), basedirpath));

           zfile_t *patch_file = zdir_patch_file (patch);
           if (verbose)
               zsys_debug("zdir_test() : added : zfile_filename (patch_file, \"\")='%s'",
                   zfile_filename (patch_file, "") );
           assert (streq (zfile_filename (patch_file, ""), filepath2));

           zdir_patch_destroy (&patch);
           zlist_destroy (&patches);

           // remove the file
           zfile_remove (newfile);
           zfile_destroy (&newfile);

           // poll for a certain timeout before giving up and failing the test.
           #ifdef CZMQ_BUILD_DRAFT_API
           polled = zpoller_wait(watch_poll, (int)zsys_file_stable_age_msec() + 150);
           #else
           polled = zpoller_wait(watch_poll, 5150);
           #endif
           assert (polled == watch);

           // wait for notification of the file being removed
           rc = zsock_recv (watch, "sp", &path, &patches);
           assert (rc == 0);

           assert (streq (path, basedirpath));
           freen (path);

           if (verbose)
               zsys_debug("zdir_test() : removed : zlist_size (patches)=%d",
                   zlist_size (patches) );
           assert (zlist_size (patches) == 1);

           patch = (zdir_patch_t *) zlist_pop (patches);
           if (verbose)
               zsys_debug("zdir_test() : removed : zdir_patch_path (patch)='%s'",
                   zdir_patch_path (patch) );
           assert (streq (zdir_patch_path (patch), basedirpath));

           patch_file = zdir_patch_file (patch);
           if (verbose)
               zsys_debug("zdir_test() : removed : zfile_filename (patch_file, \"\")='%s'",
                   zfile_filename (patch_file, "") );
           assert (streq (zfile_filename (patch_file, ""), filepath2));

           zdir_patch_destroy (&patch);
           zlist_destroy (&patches);

           zpoller_destroy (&watch_poll);
           zactor_destroy (&watch);

           // clean up by removing the test directory.
           dir = zdir_new (basedirpath, NULL);
           assert (dir);
           zdir_remove (dir, true);
           zdir_destroy (&dir);

           zstr_free (&basedirpath);
           zstr_free (&filepath1);
           zstr_free (&filepath2);

           #if defined (__WINDOWS__)
           zsys_shutdown();
           #endif

AUTHORS

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

RESOURCES

       Main web site:

       Report bugs to the email <zeromq-dev@lists.zeromq.org[1]>

COPYRIGHT

       Copyright (c) the Contributors as noted in the AUTHORS file. This file is part of CZMQ,
       the high-level C binding for 0MQ: http://czmq.zeromq.org. This Source Code Form is subject
       to the terms of the Mozilla Public License, v. 2.0. If a copy of the MPL was not
       distributed with this file, You can obtain one at http://mozilla.org/MPL/2.0/. LICENSE
       included with the czmq distribution.

NOTES

        1. zeromq-dev@lists.zeromq.org
           mailto:zeromq-dev@lists.zeromq.org