I'm using the following code from this website about how to read from a folder to get all the files. I'm then "pushing" them into a string vector.
My question is, when I read all the files, I get "." and ".." as my first to "files" read from the folder; what are these two "files"?
Furthermore, this code does achieve the goal. I'm just curious as to what these two "files" really are.
I'm using Xcode, and this is in C++.
Let me know if you need more info.
In linux and unix there is no difference between a file and a directory. Note that in the case of these dot files they are actually not "real files" though, that's another topic.
The "." is a special file in the folder which means "the current directory" and ".." is another special file which means "the parent directory".
Directories do not contain files. Directories contain names. The names are links to objects in the filesystem. The names . and .. are links to the directory and its parent, respectively.
Related
I'd like to add a directory containing .ado files to the ado-path. This directory contains several subdirectories, corresponding to different projects. The .ado files are in these subdirectories.
However, when I type adopath + directory, commands in the .ado files are not recognized by Stata. I need to enter adopath + directory/subdirectory for each subdirectory. Is there a way around it?
Stata has a rule that in addition to the directories (etc.) explicitly named in the adopath, it will also look off those in subdirectories named by an individual letter for programs whose names begin with that letter.
Thus suppose you are invoking a command whatever and your named directories include c:\ado\plus. Stata's searches will include c:\ado\plus\w if that exists and a program file has not yet been found.
However, Stata doesn't promise to search in all subdirectories and it will pay attention to the initial letter of the program name.
Having .ado files specific to a project would best be accommodated by changing to the directory involved while working on that project. If you prefer not to do that, then you need to name specific directories fully if they don't match your adopath as extended by this single letter rule.
This is a matter of personal style, but I have never thought of any ados I wrote as specific to a particular project. Do-files yes, but not ados. But your project do-file might start with additions to the adopath and finish with reversing those.
I am a beginer of QT, I tried to add an action to a toolbar and I wrote as follows:
toolbar->addAction(QIcon("/icons/new.png"), "New File");
However, the image can not be loaded. Is that related to my debug path? I can see the button, but no images.
those codes are in test.cpp and my icons folder is in the same path with test.cpp
Paths are interesting.
If you are on linux, you just specified that the root of the drive has a folder called icons, and inside it it has a file called new.png.
If you were using that kind of a path on a website, it would chop off everything to the left besides the domain and subdomain names.
example.com/path/to/some/folder/index.html, processes link to /icons/new.png, and you end up at: example.com/icons/new.png.
The best way to handle paths correctly is to use common notations for relative paths (in most cases... in some cases, absolute paths make sense).
./ means the folder that I am currently in aka the working directory.
../ means the folder above me.
A leading / means the highest folder possible or the root folder, on Unix systems. It is also akin to giving an absolute path for a file.
No leading . or .. or / means the same as ./, or from the working directory.
And there are even more rules about this. See the wiki entry:
http://en.wikipedia.org/wiki/Path_(computing)
In Qt there is also the resource system, that embeds files into the exe itself and can give you a harder-to-change image or graphic on your program.
The notation to access this is:
:/ means the root of the qresource system.
And if you do decide there is a reason to use a backslash, be sure to escape it. Normally Qt will take any input with backslashes and convert it for you on the fly to forward slashes.
So to double check that the file is there, use QFile file("icons/new.png"); followed by if(!file.exists()){ qDebug() << "File is not found!" << file.fileName(); }
Sometimes I find it helpful to see where my program is when this is happening. Either using system("dir"); or qDebug() << QDir::currentPath();
http://doc.qt.io/qt-5.5/qdir.html#currentPath
You can also see what your initial working directory is by looking at your project properties for the project in Qt Creator under:
Projects (tab) > Run (tab) > Run > Working directory:
Usually it is the root of where your source code is and where your .pro file is located.
Hope that helps.
If you are using Qt resources then you need a colon:
toolbar->addAction(QIcon(":/icons/new.png"), "New File");`
if you don't use resources then yuo should use relative path. Remember that Qt Creator uses by default "build in different place" so you must make sure that icon is deployed in respective directory.
I have a directory with these files:
one.txt
two.mp3
three.bmp
Is there any way to rename files using MoveFile() but without specifying the extension of the file (all the files have different filenames)?
If not, how can I rename these files to anything I want, when I only know the
one
two
three
?
You'll have to use the underlying OS API to scan through the directory for files and compare each filename with your desired prefix. Here is another question that shows you how to list the contents of a directory in Windows.
Once you know prefix read the filelist of the directory and find a valid filename with that prefix, and use that filename with the function.
I want to have access to all files of a folder and have a list of them and work with them.
For example: there is a folder named "new folder" and consist of files : 1.txt and 2.txt
I don't know what are in the folder new folder. So I want a list of files in it .
Hence the questions are :
1- How can I have such this list?
2- How can I delete a file (e.g 2.txt) whether i know there is file with this name or not.
3- Is it possible to figure out has a txt file been used or not (whether it is empty or not)
thanks;
I'd use Boost filesystem to analyze folder content, and remove to delete the file. You will find in filesystem tutorial some sample that will ease your work.
edit: remove(path) it's available in boost filesystem.
I'm just getting my feet wet in C++ using the Stanford CS 106B lectures available online. The assignments have the students use some custom libraries which are available for download online, although the installation instructions are gone.
While I can do the assignments in Xcode using a pre-built blank project which includes the relevant files and source trees set up, I also have TextMate on hand and thought I'd like to try coding with it, since I liked using it a lot for coding LaTeX. So far so good.
The first program I'm trying to run (a very simple ten-line program) contains an # include "genlib.h" in the first line. I have the genlib.h file, but can't seem to get either of the following to work:
Add the path to the relevant file in TextMate: When I try to add the path to the folder on my desktop (/previouspathinthelist:/Users/me/Desktop/C++\ libraries) where the file lives I get an error: /Users/me/Documents/c++ programs/powertab.cpp:9:20: error: genlib.h: No such file or directory even though the file is right there! (Maybe I should note here that the file to be imported and the program file are in two different folders).
Add the file to one of the other paths: I can't move the files using mv in terminal to usr/bin, usr/sbin, etc. because it says I don't have the proper permissions.
Is there something I'm doing wrong in setting my path to my folder in Documents? There aren't any spelling mistakes or anything since the path came straight from get info in the finder. I know this is a programming forum and not a TextMate support forum, but I thought it'd be good to know where people generally put these kinds of files on their systems.
Just put the file in the same directory as your other source files.
#include "filename"
searches the source directory first, whereas
#include <filename>
only searches the include file path.
The reason why /previouspathinthelist:/Users/me/Desktop/C++\ libraries doesn't work probably has to do with the space in the file name. It is quite possible that a backslash is not the right way to quote the space in the tool you're using. Many tools from the C/unix tradition deal rather badly with pathnames that contain space (even though the Unix kernel itself has no such problem); often you'll find that there is no single amount of quoting that will simultaneously satisfy all the tools and subsystems that use some setting. Better to avoid spaces in filenames entirely when you're doing development.