#pragma Directive in C/C++

C++ProgrammingServer Side Programming

The preprocessor directive #pragma is used to provide the additional information to the compiler in C/C++ language. This is used by the compiler to provide some special features.

Here is the syntax of #pragma directive in C/C++ language,

#pragma token_name

The table of some of #pragma directives in C/C++ language is given as follows,

Sr.No.#pragma Directives & Description
1#pragma startup
Before the execution of main(), the function specified in pragma is needed to run.
2#pragma exit
Before the end of program, the function specified in pragma is needed to run.
3#pragma warn


Used to hide the warning messages.
4#pragma GCC dependency
Checks the dates of current and other file. If other file is recent, it shows a warning message.
5#pragma GCC system_header
It treats the code of current file as if it came from system header.
6#pragma GCC poison
Used to block an identifier from the program.

Here is an example of #pragma directive in C language,

Example

#include<stdio.h>
int display();

#pragma startup display
#pragma exit display

int main() {
   printf("\nI am in main function");
   return 0;
}

int display() {
   printf("\nI am in display function");
   return 0;
}
raja
Published on 23-Oct-2018 13:53:28
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