File search APIs on Linux - c++

Question

In my project, I need to show all files on user's drive filtered by the filename with a text line. Are there any APIs to do such thing?
On Windows, I know, there're FindFirstFile and FindNextFile functions in WinAPI.
I use C++/Qt.

Answer 1

There's ftw() and linux has fts()
Besides those, you can iterate directories, using e.g. opendir8/readdir()

Answer 2

Qt provides the QDirIterator class:
QDirIterator iter("/", QDirIterator::Subdirectories);
while (iter.hasNext()) {
QString current = iter.next();
// Do something with 'current'...
}

Answer 3

If you are looking for a Unix command, you could do this :
find source_dir -name 'regex'
If you want to do it C++ style, I'd suggest to use boost::filesystem. It's a very powerfull cross platform library.
Of course, you will have to add an additional library.
Here is an example :
std::vector<std::string> list_files(const std::string& root, const bool& recursive, const std::string& filter, const bool& regularFilesOnly)
{
namespace fs = boost::filesystem;
fs::path rootPath(root);
// Throw exception if path doesn't exist or isn't a directory.
if (!fs::exists(rootPath)) {
throw std::exception("rootPath does not exist");
}
if (!fs::is_directory(rootPath)) {
throw std::exception("rootPath is not a directory.");
}
// List all the files in the directory
const std::regex regexFilter(filter);
auto fileList = std::vector<std::string>();
fs::directory_iterator end_itr;
for( fs::directory_iterator it(rootPath); it != end_itr; ++it) {
std::string filepath(it->path().string());
// For a directory
if (fs::is_directory(it->status())) {
if (recursive && it->path().string() != "..") {
// List the files in the directory
auto currentDirFiles = list_files(filepath, recursive, filter, regularFilesOnly);
// Add to the end of the current vector
fileList.insert(fileList.end(), currentDirFiles.begin(), currentDirFiles.end());
}
} else if (fs::is_regular_file(it->status())) { // For a regular file
if (filter != "" && !regex_match(filepath, regexFilter)) {
continue;
}
} else {
// something else
}
if (regularFilesOnly && !fs::is_regular_file(it->status())) {
continue;
}
// Add the file or directory to the list
fileList.push_back(filepath);
}
return fileList;
}

Answer 4

you can also use glob
http://man7.org/linux/man-pages/man3/glob.3.html
has the advantage of existing on a lot of Unices (Solaris for sure) as it is part of POSIX.
Ok, it's not C++ but pure C.

Answer 5

Look man find. find supports filtering by a mask ( -name option for examole)