what is a pragma comment?

I have seen pragma comment used to include files to a program i.e
#pragma comment(lib, "opengl32.lib")
#pragma comment(lib, "glu32.lib")

however I don't see why they dont 'just use the #include directive. What is so special about #pragma comment?
Is it just for library files and/or dlls?

ok thanks in advanced

I believe you use pragma when you include something not written in C (ie Pascal, Ada etc...) . Could be wrong, though...

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Originally posted by Shadow12345
I have seen pragma comment used to include files to a program i.e
#pragma comment(lib, "opengl32.lib")
#pragma comment(lib, "glu32.lib")

however I don't see why they dont 'just use the #include directive. What is so special about #pragma comment?
Is it just for library files and/or dlls?

ok thanks in advanced

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Those lines above link the code to the opengl libraries. Without them it has to be done in the project settings (for VC++ anyway) whihc is just more hassle. Magos seems almost correct, but I am sure its not limited to stuff that isn't written in C - could be wrong though.

>>however I don't see why they dont 'just use the #include directive.

i dont think you can #include *.lib's

"pragma" is simply used by compilers, kind of a same way as "include" .....the only difference is in between compilers and their own personal header files.......what i mean by this is that each compiler has precompiled header files that other compilers don't.........so by writing "pragma" instead of "include" you simply say that:

"include this header file in, however if you don't have such file in your library then skip it......"

hope this helps.....

matheo917

God bless #pragma!!!

NOW I KNOW HOW TO USE IT!!!!!

Ciao ;)

Ohhh yeah, what the hell does #pragma once do???

NOTE: I use MSVC++ 6

#pragma and include are two totally different things:

#include copies text into the file before compilation.
#pragma with *.lib files or dlls link your executable with this file.

#pragma once should make sure that each file is only used once in compiling.

#pragma once

This will include the header file one time. It's a multiple inclusion guard much like #ifndef , #define, #endif

However it is highly un-portable. I suggest you stick to the before mentioned method of inclusion guarding.

What does pragma stand for? I doubt it is a real name, so it has to be a shortening of something (like stdio = standard input output).

Quote:

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Originally posted by Magos
What does pragma stand for? I doubt it is a real name, so it has to be a shortening of something (like stdio = standard input output).

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