How to write c code in linux how to#
How to write c code in linux portable#
How to write c code in linux software#

Why use OS-specific functions when there is a perfectly platform-independent way of doing it? Here's a version that uses just a single header file and is portable to any platform that implements the C standard library. To run it as a command, issue the command: g++ -o hello hello.

How to write c code in linux how to#

Ill demonstrate how this is done on both Ubuntu and Red Hat distributions on how to write and compile all from the command line. Qt is a good choice.First of all, the code you wrote isn't portable, even if you get it to work. With Linux you can program in some of the most important languages on the planet, such as C++. test.exe or mono test.exe command to run the C binary Here. The aforesaid command will generate an executable file like windows. Then, open the Terminal and hit the following commands to compile the code.

For all operations that require interaction with operating system (Gui, file manipulation), use cross-platform libraries. To develop the first Mono based console application (test.cs), open any code editor like VIM and type the following code.

And maintaining one building script for all platforms may be easier than synchronizing changes across different build systems. FOr example, it works nicely with SConstructs. While in some of those systems you will have to code in flags for different compiler, it will be possible to use same script everywhere.

Try to use same build system on all platforms.

When you have to use OS-specific calls, use conditional compilation (#ifdef WIN32, etc).

Use standard functions for accessing files. For example, SDL provides types like Uint8, Qt 4 has quint32, etc. OR use types provided by cross-platform library. It is very likely that you'll need some kind of type that is guaranteed to be 4 bytes long (or something like that) - use typedef combined with conditional compilation ('#ifdef WIN32').

Do not rely on compiler-specific data types, like _int32.

For example, last time I checked '%S' behaves differently on msvc and gcc in vswprintf routine. For example, sprintf may have different additional formats that are implemented differently on different platforms. This may be of interest to you a someone learning to write C code or an administrator wanting to more about permissions. Using these values in a simple C program that we can use to demonstrate the use of the SUID permission. (I know that it is supposed to be a bad practice, but in some scenarios this is useful) They have slightly different implementations, extensions, and different number of parameters. The REAL UID being the UID of the user and the EFFECTIVE UID represents the userР В Р вЂ Р В РІР‚С™Р Р†РІР‚С›РЎС›s whose rights we use.

Be very careful if you decide to use C-style routines (like sprintf) in C++ code.

Which, of course, won't be available on other platforms. For example, MS compiler provides multiple 'safe' (like strcpy_s) versions of standard C-style routines. This more applicable to C library functions, though.

Do not use extensions to standard library (provided by compiler developer).

Do not use compiler-specific pragmas, macros and extensions.

There are many ways and many languages to create a. And you should not assume that pointer is 4 bytes large (passing user data pointer into api call scenario) - it will be 8 bytes on 64 bit. On Windows, the Win32 API LoadLibrary is used while on Linux gcc compiler, the dlopen function is used. Also you'd have to use the length to terminate the loop, instead of checking each character. In that case you'd need a loop like the one you show above, but with nwritten write( USB, cmd + spot, commandlength - spot). Use sizeof (if you need it), or try to avoid having to use size of any type in your code. The code you suggest for sending int nwritten write( USB, cmd, sizeof(cmd) -1) doesn't really work for large buffers.

For example, on msvc sizeof(wchar_t) is 2 bytes.

Do not rely on sizes of standard types.

For example, certain versions of ms compiler have a limit on sizes of string constants, which gcc doesn't have.

Even if your code is perfect, compiler might have some kind of unexpected quirk. 'microsoft compiler'), and a linux installation with g++ (or use virtual machine).

How to write c code in linux software#

If you're doing cross-platform software for windows windows/linux, keep around mingw, visual studio express (i.e. Keep several compilers nearby, test code regularly on target platforms.The three most common and widely used operating systems share thi. What are the things that I should keep in mind to write portable code? We know that an operating system is considered as the backbone of any system that you may use.