C Programming

strcmp is a function in C which is used to compared two strings that is array of characters and returns if the first array is greater, smaller or equal to the second array

qsort in C is an in-built function for sorting array of any data types including structs. It, internally, uses a variant o Quick Sort and is a part of stdlib.h

ctype.h header file of the C Programming Language provide several functions that are used to testing different characters and changing some properties.

Auto is a storage class/ keyword in C Programming language which is used to declare a local variable, forward declaration of nested functions and non-contiguous memory allocation.

Volatile in C programming language is a keyword which is used with variables to inform the compiler not to apply any optimizations to code dealing with the variable.

Extern is a keyword in C programming language which is used to declare a global variable that is a variable without any memory assigned to it. It is used to declare variables and functions in header files.

Register is a keyword in C which suggests the system to use register as a memory for a variable instead of RAM. This accelerates the reading and writing of memory

_bool is a keyword in C Programming language representing boolean data type. It is an alternative to bool in C.

We have listed all major C compilers that has been in use. Some compilers were developed in 1980s (GNU GCC) while the recent ones are from 2017 (AOCC).

Printf() and Scanf() are inbuilt library functions in C language that perform formatted input and formatted output functions. These functions are defined and declared in stdio.h header file.

#include is a preprocessor directive in C and C++ to include the code from other files (header files + C/ C++ code) in the current file.

To check the operating system of the host in a C or C++ code, we need to check the macros defined by the compiler (GNU GCC or G++). For example, on Windows platform, the compiler has a special macro named _WIN32 defined.

#error is a preprocessor directive in C which is used to raise an error during compilation and terminate the process.

Compilation is the process of converting a code in a programming language (C in our case) to machine code. In this process, the code goes through different steps depending upon the compiler and language. We will explore the compilation steps in C.

To check if an header file has been included or not in a C or C++ code, we need to check if the macro defined in the header file is being defined in the client code.

#warning is a preprocessor directive in C which is used to raise compilation warnings for various situations. It is different from #error directive in that #warning will not cancel the compilation process while #error will cancel it.

#undef is a preprocessor directive to remove an existing macro. It is useful as the only way to update an existing macro is to delete it (using undef) and create a new macro (using define).

#define is a preprocessor directive in C which is used to define macros. Macros are code framents which has been given a name.

ifdef is an include guard. ifndef can be seen as if defined then do this till endif. It is opposite of [ifndef directive

ifndef directive is a define directive in C which checks if a MACRO has been defined previously or not. If it has not been defined, it will execute a set of commands. It is followed by endif.

In this article, we explored the core reasons for memory leak in C with examples and how we can prevent such situations while writing C code

Limits.h header file in C is used to determine the set limits of variable data stypes. Macros defined in limits.h header file