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c++ Programming Glossary: ifndef

#pragma - help understanding

http://stackoverflow.com/questions/1263521/pragma-help-understanding

help understanding Can anyone help me understand #pragma ifndef TARGET_OS_LINUX #pragma once endif What when where why an example..

Why are #ifndef and #define used in c++ header files

http://stackoverflow.com/questions/1653958/why-are-ifndef-and-define-used-in-c-header-files

are #ifndef and #define used in c header files I have been seeing code.. code like this usually in the start of header files #ifndef HEADERFILE_H #define HEADERFILE_H and at the end of the file.. of the page. When the code is included again the first ifndef fails resulting in a blank file. That prevent double declaration..

Why isn't C/C++'s “#pragma once” an ISO standard?

http://stackoverflow.com/questions/1695807/why-isnt-c-cs-pragma-once-an-iso-standard

file I should rename all the include guards as well in the ifndef define and ideally endif's comment . Annoying. Preprocessor..

macros as arguments to preprocessor directives

http://stackoverflow.com/questions/1736654/macros-as-arguments-to-preprocessor-directives

new line group # ifdef identifier new line group # ifndef identifier new line group # elif constant expression new line..

How are circular #includes resolved?

http://stackoverflow.com/questions/3127171/how-are-circular-includes-resolved

question Typically you protect your include file with an ifndef define that corresponds to the file name. This doesn't prevent.. included again but it does prevent the contents inside the ifndef from being used and triggering the recursive includes again... being used and triggering the recursive includes again. #ifndef HEADER_1_h #define HEADER_1_h #include 2.h rest of 1.h #endif..

What techniques can be used to speed up C++ compilation times?

http://stackoverflow.com/questions/373142/what-techniques-can-be-used-to-speed-up-c-compilation-times

more than once in a single translation unit. #pragma once #ifndef filename_h #define filename_h Header declarations definitions.. definitions #endif By using both the pragma and the ifndef you get the portability of the plain macro solution as well..

the role of #ifdef and #ifndef

http://stackoverflow.com/questions/3744608/the-role-of-ifdef-and-ifndef

role of #ifdef and #ifndef #define one 0 #ifdef one printf one is defined #ifndef one.. #ifndef #define one 0 #ifdef one printf one is defined #ifndef one printf one is not defined In this what is the role of #ifdef.. one is not defined In this what is the role of #ifdef and #ifndef and what's the output c c preprocessor share improve this..

Why are there digraphs in C and C++? [duplicate]

http://stackoverflow.com/questions/432443/why-are-there-digraphs-in-c-and-c

and C . The following is a valid program include stdio.h ifndef BUFSIZE define BUFSIZE 512 endif void copy char d const char..

Multiple Defined Symbols C++ error

http://stackoverflow.com/questions/5370413/multiple-defined-symbols-c-error

Defined Symbols C error I thought ifndef something #define something body #endif solved this error so.. error so I'm not sure why this is happening. Library.h #ifndef __LIBRARY__ #define __LIBRARY__ #include iostream #include string.. std #endif __LIBRARY__ globals.h global variables #ifndef __GLOBAL__ #define __GLOBAL__ #include vector #include iostream..

C++ - How to set file permissions (cross platform)

http://stackoverflow.com/questions/592448/c-how-to-set-file-permissions-cross-platform

static const mode_t S_IXUSR 0x00400000 does nothing # ifndef STRICT_UGO_PERMISSIONS static const mode_t S_IRGRP mode_t _S_IREAD..