c++ - readdir(): re-reading certain files - Stack Overflow
Understanding recursive subroutines was one of the major break-through in Then, we use the opendir function to open the directory, and then use the readdir . Walk a directory/Non-recursively (read a single directory). readdirSync dir for fn in fns . pad count open-dir if drop r> pad c! exit then (dirid). The opendir() system call function is used to open a directory and to return a pointer on this directory. Let's take an example of the using of the opendir system call function. First, we UNIX & GNU/Linux - System calls - fork() up UNIX & GNU /Linux - System calls - readdir() › Recursion Relationships.
Then we print whatever we found in the directory. It will print the content.
inotify and missing events on linux kernel
That is we need out function to recursively call itself. We would like to see an output like this: The full script will look like this: Let's see another approach that might help further see how the recursion works.Java: Recursive traversal through a file tree
Top down approach In this approach we start by creating a subroutine called traverse that can get the name of a directory or a file and print it out. Each item is again needs the exact same treatment as the current one gets, so we can call traverse for each item in the while loop: This is the additional code: It could go on forever but we know at some point it will reach the leafs of the tree, a directory in which there are no more directories.
Then it won't call itself again, and slowly it will return to the top-most level. The condition when the recursive function is not called again, in our case the directories without subdirectories, is usually called the halting condition of the recursion. A function without such halting condition, will recurse forever. Well, not exactly forever as most system would run out of memory before that. In addition Perl will give a warning Deep recursion on subroutine when the code reaches level depth.
If use warnings; is in effect. The full code of the top-down approach looks like this: A recursive function has two major parts. The first one checks for some condition and returns if that condition was met. This is called the halting condition, or stop condition.
Then at some later point in the function it calls itself with a different set of parameters than it was called earlier. Other solution using a queue Besides using recursion this problem can also be solved by using a queue. Originally Posted by neonsignal One potential issue is that a file can be moved ie renamedwhich is common for applications that make temporary files eg decompression to a temporary, then rename to the actual name.
So it may be necessary to check for MOVE events in some circumstances. Originally Posted by neonsignal The inotifywatch tool is not going to report any directories that are empty, since they will not have any reportable events; this means that a line count on the output isn't necessarily going to match the directories created.
It would be more concerning if the count is not consistently the same every time. I know that inotifywatch only shows directories in its output.
Today, I reran the test case as described above.
Understanding recursive subroutines - traversing a directory tree
The first time I see directories listed in output. It does seem to fluctuate even given the fact that it is the same zip every time. I tried invoking a sync command in another terminal just to be sure the output. Originally Posted by neonsignal Not clear that 'blocking' is required here. What I mean here is that I expect to be able to know when the directory is ready to report any events that happen to it.