In C++Builder 10.3 I have a code with fopen() function. I know that this function is declared in stdio.h. In my code this header is not included explicitly but, I guess implicitly in Vcl.h. Trying to confirm it I opened Vcl.h but found no stdio.h there. Instead I found many other header files. Is there a way to dig out where stdio.h file is hidden?
Due to problems with new compiler first make sure that you use "classic Borland compiler". Then write fopen in text editor. Press CRTL + left click on fopen and it will open stdio.h. In my case it is located in C:\Program Files (x86)\Embarcadero\Studio\20.0\include\windows\crtl folder.
Related
Is there a way to see what's inside the stdio.h or how it's implemented?
I learned that the standard functions are declared in the stdio.h file
and I can't find it in my computer
plus I heard that there is another file where the body of the functions are all written,
which is called the stdio.c file.
Can anyone tell me WHERE this file is in my computer (I am using gcc compilier)
or anyway to see how it is implemented?
As far as I know the c++ header files are stored in C:\Program Files (x86)\Windows Kits\10\Include\"some_version"\ucrt for Windows, and in /usr/include for linux. There you can find the stdio.h file and any other of the standard c++ header files.
Otherwise looking on the internet for stdio.h source code is also an option
Can we remove .h extensions while we define our own header file in c++? like in case of standard header files in c++.
I have created a header file and named it add.h and tried including it using #include "add" but it didn't work.
after following up the comments and answers:
using codeblocks ide
i have created a "add" of type File and tried it including in my source file and it worked. attaching the snapshot below.
the aim of my question is to ask if userdefined header files can also omit .h extensions and how?
i am really trying to explore this fact and don't have a good understanding of how compilers stores standard header files.
A easy to understood conclusion is really appreciated
Thankyou.
Can we remove .h extensions while we define our own header file in c++?
Sure, as long as that matches the filename of the file. As far as the language is concerned, the name of the file is largely irrelevant.
However, .h or similar such as .hpp is conventional, and helps the reader of the source to understand what the file is used for. This is an important consideration.
Another consideration is that some tools use the filename as a heuristic to determine the purpose of the file. For example, your IDE might not assume that the file contains C++ code, and thus not enable C++ features such as source analysis unless you follow a common naming convention.
I have created a header file and named it add.h and tried it including in source file using #include "add" but it didn't work.i know i am missing some important concepts here.
What you're missing is that the include directive must match the name of the file. If you include "add", then you must name the file add, not add.h. If you name a file add.h, then you must include "add.h", not "add".
Can we remove .h extensions while we define our own header file in c++? like in case of standard header files in c++.
You've misunderstood how the files in the stardard library are named. The header file iostream is actually named iostream and not iostream.hpp or iostream.h (unless you use a very old compiler).
I have created a header file and named it add.h and tried including it using #include "add" but it didn't work.
The reason that doesn't work is because the pre-compiler tries to read the file add and you've named the file add.h.
I'm very new in Arduino, so maybe my question will be stupid but I have to ask it!
I made a mqtt client for my nodeMcu chip, and I have this error
/Users/mikevorisis/Downloads/pubsubclient-master/examples/mqtt_esp8266/mqtt_esp8266.ino:27:26:
fatal error: PubSubClient.h: No such file or directory #include
I downloaded the original project from github and I tried to compile the example it has in examples/mqtt_esp8266 but again I have the same problem.
I also tried to put the PubSubClient.h in the same folder but again I have the same problem.
Any ideas?
Thanks in advance.
The file you have downloaded and included in your project is probably not actually a header file. You probably copied the contents of it from github and pasted it into a text document which you saved as a text file with the extension ".h".
It now has the extension "filename.h.txt". The name and extension need to be only "filename.h". Use save as, and select "all files" when saving, and name it "filename.h". Be sure to retype the filename, or it can be auto-filled with the already existing "filename.h.txt" (even if you don's see it!).
If the file now has the right extension, put it in the same folder as your source code file. You can see which directory your source file is in by going to "save as" in your IDE.
A problem you might run into after this is missing definitions. You see, when you use libraries in the form of header files, each header file must usually (in this case, yes) be accompanied by a .cpp file (not necessarily with the same name). The reason for this is that the header file contains declarations, and the cpp file the definitions for said declarations. In other words, the header file is an overview of the facilities available in the library, and the cpp file actually implements the guts of it.
Edit: The example you are trying to run also has #include <ESP8266WiFi.h>, a file that is not available in the github repository that you referred to. I assume that this is a library for a WiFi module or such that you can get elsewhere (manufacturer, other git's or maybe it comes with the Arduino IDE?). In other words, you also need to add its header and (probably) .cpp file to your source directory.
In code blocks their default file is main.cbp so I usually change it to main.cpp. But there doesn't seem to be a difference between their performances. But then again I just began coding in C++ so I'd like to know if there are any differences before I get too deep.
.cbp is the extension for a codeblocks solution file. Usually the project file will contain the .cpp file. chp files dont contain the actual source code but the procedure for codeblocks to associate files.
In a nutshell, .cpp contains the source code while cbp files dont.
Why do you have to know about that?
Answer: when passing source code, cpp file is the only format that can be opened for IDE other than codeblocks eg. Dev C++
I am trying to compile the Scintilla control with MSVC++ 2010 Express Edition, and it's quite painful getting it to work right because I need a bunch of files. When compiling SString.h, I noticed this:
#include <crtdll/stddef.h>
I am no C++ programmer, but I do understand what
#include <xxx.h>
means, but what does the the that include mean? I get the following error with it:
Error 1 error C1083: Cannot open include file: 'crtdll/stddef.h': No such file or directory f\scintilla\lexers\sstring.h 44
Any help on how I could fix it would be appreciated.
If I am not mistaken, that is just a relative path. In other words, Visual Studio will look for stddef.h in the crtdll subdirectory of, probably, the root directory of the project.
By using the preceding function, you are summoning, and subsequently inserting a header file into your current source code.
In the case of #include <crtdll/stddef.h> you will be inserting the stddef.h header file from the crtdll directory (which should be a child folder defined in your compiler as the holding pen for header files) during the compilation and linking of your program.
By inserting the stddef.h header file into your source you are giving your program the capability to wield NULL pointer constants, which are exceedingly useful in some of the more advanced programs you may or may not have come across.
Good luck with your program!
I am no C++ programmer, but I do understand what
are you sure?
include with <> searches the include paths for the specified file and copies the content the content of that file in your .cpp.
So you are just missing the crtdll/stddef.h file, however stddef.h actually belongs to the C standardlibrary so you might replace it with #include in C or #include in C++
The easiest way would be to check your include directories. crtdll is the C standard library provided by msvc, so maybe you have to add the parent folder of your standard library include directory
This means that stddef.h needs to be included from the crtdll folder.
You need to check your include directories for Visual C++ projects to see that which are the default directories from where Visual Studio looks up for header files.
To fix this error, see that at which path have you installed the Scintilla control. The crtdll folder will be there most probably. And then, add this folder to your visual studio include directories.
You can set it in the following project properties dialog:
Here http://i56.tinypic.com/2zo9guh.jpg