H file icon

H File Extension

C/C++/Objective-C Header Format

What is H file?

H is a file generated when working with C, C++ or Objective-C languages.

Contents of H files

Files with H extension contain function declarations or macros, and thus can hold such data as:

  • variable and constant value declarations,
  • reference to other files,
  • library calls

In practice H files are used for holding code that is frequently used. This allows for better source code legibility and programmer efficiency. Functions and macros defined in H files makes the them reusable across projects and facilitates code sharing. This also makes it easier to update the code as it is stored ia a single, well-known place.

How are H files used?

Storing frequently used code in H files makes is easier to access and add to project source code. During code compilation to machine code, first the compiler program identifies declarations in H files and incorporates the definitions in the compiled code as H libraries and then continues the compilation. In this way related H files do not have to be distributed with the source code because the compiler can access needed definition from system libraries.

Programs which support H file extension

Below you will find an index of software programs that can be used to open H files divided into 3 categories according to system platform supported. H files can be encountered on all system platforms, including mobile, yet there is no guarantee each will properly support such files.

Updated: 12/11/2023

How to open file with H extension?

Being unable to open files with H extension can be have various origins. Fortunately, most common problems with H files can be solved without in-depth IT knowledge, and most importantly, in a matter of minutes. The list below will guide you through the process of addressing the encountered problem.

Step 1. Get the Microsoft Visual Studio

Install software to open H file The most common reason for such problems is the lack of proper applications that supports H files installed on the system. This one is an easy one. Select Microsoft Visual Studio or one of the recommended programs (for example, Borland C++, Eclipse IDE, Dev-C++) and download it from appropriate source and install on your system. Above you will find a complete listing of programs that support H files, classified according to system platforms for which they are available. If you want to download Microsoft Visual Studio installer in the most secured manner, we suggest you visit Microsoft Corporation website and download from their official repositories.

Step 2. Verify the you have the latest version of Microsoft Visual Studio

Update software that support file extension HYou still cannot access H files although Microsoft Visual Studio is installed on your system? Make sure that the software is up to date. It may also happen that software creators by updating their applications add compatibility with other, newer file formats. If you have an older version of Microsoft Visual Studio installed, it may not support H format. All of the file formats that were handled just fine by the previous versions of given program should be also possible to open using Microsoft Visual Studio.

Step 3. Associate C/C++/Objective-C Header Format files with Microsoft Visual Studio

If you have the latest version of Microsoft Visual Studio installed and the problem persists, select it as the default program to be used to manage H on your device. The next step should pose no problems. The procedure is straightforward and largely system-independent

Associate software with H file on Windows

The procedure to change the default program in Windows

  • Clicking the H with right mouse button will bring a menu from which you should select the Open with option
  • Next, select the Choose another app option and then using More apps open the list of available applications
  • Finally select Look for another app on this PC, point to the folder where Microsoft Visual Studio is installed, check the Always use this app to open H files box and conform your selection by clicking OK button
Associate software with H file on Mac

The procedure to change the default program in Mac OS

  • Right-click the H file and select Information
  • Proceed to the Open with section. If its closed, click the title to access available options
  • Select the appropriate software and save your settings by clicking Change all
  • Finally, a This change will be applied to all files with H extension message should pop-up. Click Continue button in order to confirm your choice.

Step 4. Ensure that the H file is complete and free of errors

You closely followed the steps listed in points 1-3, but the problem is still present? You should check whether the file is a proper H file. Being unable to access the file can be related to various issues.

Check H file for viruses
1. Verify that the H in question is not infected with a computer virus

If the file is infected, the malware that resides in the H file hinders attempts to open it. Scan the H file as well as your computer for malware or viruses. If the H file is indeed infected follow the instructions below.

2. Verify that the H file’s structure is intact

If you obtained the problematic H file from a third party, ask them to supply you with another copy. The file might have been copied erroneously and the data lost integrity, which precludes from accessing the file. When downloading the file with H extension from the internet an error may occurred resulting in incomplete file. Try downloading the file again.

3. Verify whether your account has administrative rights

Sometimes in order to access files user need to have administrative privileges. Log out of your current account and log in to an account with sufficient access privileges. Then open the C/C++/Objective-C Header Format file.

4. Check whether your system can handle Microsoft Visual Studio

If the systems has insufficient resources to open H files, try closing all currently running applications and try again.

5. Ensure that you have the latest drivers and system updates and patches installed

Up-to-date system and drivers not only makes your computer more secure, but also may solve problems with C/C++/Objective-C Header Format file. It may be the case that the H files work properly with updated software that addresses some system bugs.

Do you want to help?

If you have additional information about the H file, we will be grateful if you share it with our users. To do this, use the form here and send us your information on H file.

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