What is an example of preprocessor?
Preprocessor programs provide preprocessors directives which tell the compiler to preprocess the source code before compiling. All of these preprocessor directives begin with a ‘#’ (hash) symbol. Examples of some preprocessor directives are: #include, #define, #ifndef etc.
What is the purpose of the preprocessor?
In computer science, a preprocessor (or precompiler) is a program that processes its input data to produce output that is used as input to another program. The output is said to be a preprocessed form of the input data, which is often used by some subsequent programs like compilers.
What is preprocessor include?
The #include preprocessor directive is used to paste code of given file into current file. It is used include system-defined and user-defined header files. If included file is not found, compiler renders error. There are two variants to use #include directive.
What are the preprocessor commands?
Following are the preprocessor commands in C programming language…
- #define. #define is used to create symbolic constants (known as macros) in C programming language.
- #undef. #undef is used to destroy a macro that was already created using #define.
- #ifdef.
- #ifndef.
- #if.
- #else.
- #elif.
- #endif.
Why preprocessing directives are used eg #include Iostream?
The #include directive allows a programmer to include contents of one file inside another file. This is commonly used to separate information needed by more than one part of a program into its own file so that it can be included again and again without having to re-type all the source code into each file.
What is C structure?
By Chaitanya Singh | Filed Under: c-programming. Structure is a group of variables of different data types represented by a single name. Lets take an example to understand the need of a structure in C programming. Lets say we need to store the data of students like student name, age, address, id etc.
Which one of the following functions does a preprocessor perform?
Explanation: The preprocessor provides the ability for the inclusion of header files, macro expansions, conditional compilation, and line control.
Why preprocessor directives are needed?
Preprocessor directives, such as #define and #ifdef , are typically used to make source programs easy to change and easy to compile in different execution environments. Directives in the source file tell the preprocessor to take specific actions. Preprocessor lines are recognized and carried out before macro expansion.
Why we use include Stdio H?
“stdio” stands for standard input-output. stdio. h contains prototypes for standard input/output functions like scanf/printf. Without including this file, one will not be able to read input from keyboard or write output to screen.
What are the two forms of #include directive?
Here are the two types of file that can be included using #include: Header File or Standard files: This is a file which contains C/C++ function declarations and macro definitions to be shared between several source files.
What are preprocessor directives or statements?
Preprocessor directives are lines included in a program that begin with the character #, which make them different from a typical source code text. Preprocessor directives change the text of the source code and the result is a new source code without these directives.
Which of the following is not preprocessor directive?
Ans: #elseif is not any preprocessor directive, but #elif is.
Which is the implicit preprocessor option in GCC?
-fpreprocessed is implicit if the input file has one of the extensions ‘ .i ’, ‘ .ii ’ or ‘ .mi ’. These are the extensions that GCC uses for preprocessed files created by -save-temps .
What is the behavior of the preprocessor option?
The option’s behavior depends on the -E and -fpreprocessed options. With -E, preprocessing is limited to the handling of directives such as #define, #ifdef, and #error. Other preprocessor operations, such as macro expansion and trigraph conversion are not performed.
Where does the process file appear in the preprocessor?
Process file as if #include “file” appeared as the first line of the primary source file. However, the first directory searched for file is the preprocessor’s working directory instead of the directory containing the main source file.
Do you use quoting syntax when invoking the preprocessor?
In particular, the definition is truncated by embedded newline characters. If you are invoking the preprocessor from a shell or shell-like program you may need to use the shell’s quoting syntax to protect characters such as spaces that have a meaning in the shell syntax.