Boost library in C++
Introduction:
The Boost C++ Libraries are a group of excellent, peer-reviewed, and portable C++ libraries that go beyond what the C++ Standard Library provides in terms of supporting various tasks and functionalities. These libraries include a wide range of components, such as data structures, algorithms, I/O, threading, and more, in an effort to enhance and simplify C++ development.
Key Points:
- Portability: Boost is a flexible option for cross-platform development because it is made to run on a variety of systems and compilers.
- Community-Driven: As a community-driven project, Boost relies on volunteers who belong to the C++ community to maintain its libraries. This guarantees that the libraries are updated and improved continuously.
- Standalone and Header-Only Libraries: Boost has both standalone and header-only libraries. While standalone libraries may need compiling and linking, header-only libraries may be included by adding #include directives.
- Libraries are available from Boost in a number of categories, including:
- Libraries that support different container types and information structures like arrays, lists, and trees are available for containers.
- Algorithms: Improvements and extensions to the default algorithms in C++.
- Concurrency: Tools for concurrent programming and multithreading.
- A library for interacting with the filesystem is called the filesystem.
- Support for regular expressions.
- Upgrades to C++'s smart pointers are known as smart pointers.
- Numeric: Computer libraries for mathematics and numbers.
- Tools for object serialisation and deserialization are known as serialisation.
- A C++ testing framework is available.
- I/O: Support for input/output that goes beyond the C++ Standard Library
Example:
#include <iostream>
#include <boost/date_time/posix_time/posix_time.hpp>
int main() {
boost::posix_time::ptime currentTime = boost::posix_time::second_clock::local_time();
std::string formattedTime = boost::posix_time::to_simple_string(currentTime);
std::cout << "Current date and time: " << formattedTime << std::endl;
return 0;
}
Output:
![Boost library in C++](https://static.tutorialandexample.com/cpp/boost-library-in-cpp1.png)
Download and installation:
- Install Boost:
Go to the "Download" section on the official Boost website at https://www.boost.org/. Links to the most recent Boost release are available.
- Select the Installation Technique:
The libraries from Boost can be installed in a number of ways:
- Pre-built Binaries: You can install pre-built Boost binaries from some platforms and package managers. For instance, to install Boost on Linux, you could use apt, yum, or dnf. Pre-built binaries are available for Windows download from the Boost website.
- Self-Building: You can obtain the Boost source code if pre-built binaries are not offered or if you prefer to build Boost yourself. Although it requires compilation, this solution is the most flexible.
- Build Boost, if required:
You must compile the Boost source code if you decided to download it. Follow these steps to accomplish this:
- Extract the Boost source code that you downloaded to the directory of your choice.
- Go to the Boost source directory by launching a terminal or command prompt.
- Run the bootstrap script (bootstrap.sh on Unix-like systems, bootstrap.bat on Windows):
./bootstrap.sh # Unix-like systems
bootstrap.bat # Windows
- Run the b2 command to create the Boost libraries:
./b2 # Unix-like systems
b2.exe # Windows
- Installation:
The stage directory inside the Boost source directory is where the Boost libraries will by default be created. By using the following command, you may decide whether to install them in a system-wide place or a specific one:
./b2 install --prefix=/path/to/installation/directory
- Installation Check:
You can attempt constructing a straightforward C++ programme that requires and includes a Boost library to see if Boost has been successfully installed. If the programme runs and compiles without any issues, Boost was probably installed properly.
Usage of boost in C++:
- Boost.Date_Time: Working with Date and Time
#include <iostream>
#include <boost/date_time/posix_time/posix_time.hpp>
int main() {
boost::posix_time::ptime currentTime = boost::posix_time::second_clock::local_time();
std::string formattedTime = boost::posix_time::to_simple_string(currentTime);
std::cout << "Current date and time: " << formattedTime << std::endl;
return 0;
}
- Boost.Algorithms: Using Boost Algorithms
#include <iostream>
#include <vector>
#include <boost/algorithm/string.hpp>
int main() {
std::string str = "Boost C++ Libraries";
boost::to_upper(str);
std::cout << "Uppercase: " << str << std::endl;
std::vector<int> numbers = {1, 2, 3, 4, 5};
boost::algorithm::reverse(numbers);
std::cout << "Reversed numbers: ";
for (int num : numbers) {
std::cout << num << " ";
}
std::cout << std::endl;
return 0;
}
- Boost.Thread: Multithreading and Concurrency
#include <iostream>
#include <boost/thread/thread.hpp>
void worker_function() {
for (int i = 0; i < 5; ++i) {
std::cout << "Working... " << i << std::endl;
boost::this_thread::sleep_for(boost::chrono::milliseconds(1000));
}
}
int main() {
boost::thread worker_thread(worker_function);
worker_thread.join();
std::cout << "Worker thread has finished." << std::endl;
return 0;
}
- Boost.Filesystem: File and Directory Operations
#include <iostream>
#include <boost/filesystem.hpp>
int main() {
boost::filesystem::path filePath("example.txt");
if (boost::filesystem::exists(filePath)) {
std::cout << "File exists." << std::endl;
std::cout << "File size: " << boost::filesystem::file_size(filePath) << " bytes." << std::endl;
} else {
std::cout << "File does not exist." << std::endl;
}
return 0;
}
- Boost.Regex: Regular Expressions
#include <iostream>
#include <boost/regex.hpp>
int main() {
boost::regex pattern("[0-9]+");
std::string text = "Boost 123 C++ 456 Libraries";
boost::sregex_iterator it(text.begin(), text.end(), pattern);
boost::sregex_iterator end;
while (it != end) {
std::cout << "Match: " << it->str() << std::endl;
++it;
}
return 0;
}