extern

I've got a file that defines very basic IO functions and I want to create another file that uses this file. Is there a way to link these two files up? prints.asm: os_return: ;some code to return to os print_AnInt: ;some code to output an int, including negatives - gets param from stack print_AChar: ;some code to output a char - gets param from stack usingPrintTest.asm: main: push qword 'a' call print_AChar ;gets this from prints.asm somehow (that's my question) call os_return ;and this too.. Note these aren't the actual files... They're just used to explain my problem :) Thanks! Sure - you

This is from the <iostream> : namespace std { extern istream cin; ///< Linked to standard input extern ostream cout; ... It seems by using extern the data types defined in other namespaces will just be available? extern is used to refer to a variable defined in a different compilation unit (for now, you can think of a compilation unit as a .cpp file). The statements in your example declare rather than define cin and cout . It is telling the compiler that the definition of these objects is found in another compilation unit (where they are not declared as extern ). extern means "these variables

问题背景： 现在在搞PC端应用开发，我们开发中需要调用系统的窗口以及需要最大化最小化，缩放窗口拖拽窗口，以及设置窗口位置，去边框等功能 解决根据： 使用user32.dll解决 具体功能： Unity中对Windows窗口设置 <1>.unity中调用打开文件窗口和保存窗口： 调用Comdlg32.dll中方法 1 using System; 2 using System.Collections.Generic; 3 using System.Linq; 4 using System.Runtime.InteropServices; 5 using System.Text; 6 using System.Threading.Tasks; 7 8 namespace Tx3d.Ventilation 9 { 10 /// <summary> 11 /// 场景窗口类型基类 12 /// </summary> 13 [StructLayout(LayoutKind.Sequential, CharSet = CharSet.Auto)] 14 public class SceneWindows 15 { 16 public int structSize = 0; 17 public IntPtr dlgOwner = IntPtr.Zero; 18 public IntPtr

I read a few posts and concluded that extern tells compiler that "This function exists, but the code for it is somewhere else. Don't panic." But how does the linker know where the function is defined. My CASE:- I am working on Keil uvision 4. There is a header file grlib.h and the main function is in grlib_demo.c(it includes grlib.h). Now, there is a function GrCircleDraw() which is defined in Circle.c and called in grlib_demo.c, there is also a statement extern void GrCircleDraw(all arguments); in grlib.h. My query is how linker knows where the definition of GrCircleDraw() is since Circle.c

Pardon me if this sounds a question that has been asked many times but I assure you this is a little different. I use Codeblocks for C programming and lately I have started to wonder why would someone use a header file in C. I understand it is used for declaring and/or defining variables structures. But here is something i tried and now I am confused. I have a header file named test1.h #ifndef TEST1_H_INCLUDED #define TEST1_H_INCLUDED static int testvar = 233; extern int one; extern void show(); #endif // TEST1_H_INCLUDED and two other files headertest.c #include"test1.h" #include<stdio.h> int

前面已经写了系列一： https://blog.csdn.net/yongjiankuang/article/details/102470457 ，系列一主要是tensorflow对mnist进行模型训练，然后将训练好的参数导出来。本博文就是利用导出来的参数，搭建c代码的mnist前向网络。具体实现如下： #ifndef __COMMON_H_ #define __COMMON_H_ #include <iostream> #include <stdint.h> using namespace std; #define u8 unsigned char #define s8 char #define u16 unsigned short #define s16 short #define u32 unsigned int #define s32 int #define f32 float extern f32 W_conv1_0[]; extern f32 b_conv1_0[]; extern f32 W_conv2_0[]; extern f32 b_conv2_0[]; extern f32 W_fc1_0[]; extern f32 b_fc1_0[]; extern f32 W_fc2_0[]; extern f32 b_fc2_0[]; #endif layer