1、父子进程通信pipe编程流程
-创建管道
-设置进程的输出到管道
-创建进程
-关闭管道写句柄
-读管道读句柄，把数据读到一个buffer里
2、注意事项
-读管道数据的时候，一定要关闭写句柄；
-父子进程通信时，句柄的传递多通过继承来完成，父进程允许这些句柄为子进程继承；创建子进程，是否继承的属性要设置为true；
// pdfprintconsole.cpp : 此文件包含 "main" 函数。程序执行将在此处开始并结束。
//
#include "pch.h"
#include <iostream>
#include <Windows.h>
#include<tchar.h>
#include <string.h>
int main()
{
int page_index = 0;
char currentBuff[1000] = { 0 };
char cachFileName[1000] = { 0 };
char printCommand[1000] = { 0 };
char command[500] = { 0 };
HANDLE handle = 0;
BOOL bTest = 0;
SECURITY_ATTRIBUTES sa = { 0 };
DWORD dwNumberOfBytesRead = 0;
CHAR szBuffer[10000] = { 0 };
DWORD ret = 0;
HANDLE hPipeOutputRead = NULL;
HANDLE hPipeOutputWrite = NULL;
STARTUPINFOA si = { 0 };
PROCESS_INFORMATION pi = { 0 };
sa.bInheritHandle = TRUE; // TRUE为管道可以被子进程所继承
sa.lpSecurityDescriptor = NULL; // 默认为NULL
sa.nLength = sizeof(SECURITY_ATTRIBUTES);
// Create pipe for standard output redirection.
CreatePipe(&hPipeOutputRead, // read handle
&hPipeOutputWrite, // write handle
&sa, // security attributes
0 // number of bytes reserved for pipe - 0 default
);
// Make child process use hPipeOutputWrite as standard out,
// and make sure it does not show on screen.
si.cb = sizeof(si);
si.dwFlags = STARTF_USESHOWWINDOW | STARTF_USESTDHANDLES;
si.wShowWindow = SW_HIDE;
//si.hStdInput = hPipeInputRead;
si.hStdOutput = hPipeOutputWrite;
si.hStdError = hPipeOutputWrite;
//strcpy_s(command, " -printer \"FX DocuCentre S2011\" -paper 9 -printermargins C:\\Users\\QJ\\Desktop\\f3044688ce88a4b0a78c16ba85076570-5378-0010-0.png");
strcpy_s(command," -printer \"FX DocuCentre S2011\" -listpapers");
//一共执行三次
for (int i = 0; i < 3; i++)
{
if (!CreateProcessA("C:\\Users\\QJ\\source\\repos\\WindowsFormsApp1\\x64\\Debug\\pdfprint.exe", command, NULL, NULL, TRUE, NULL, NULL, NULL, &si, &pi))
{
//AfxMessageBox("缺失pdfprint.exe文件",0,0);
break;
}
else
{
HANDLE hProcess = pi.hProcess;
//等待进程退出 //CloseHandle(hPipeOutputRead);
while (WaitForSingleObject(hProcess, INFINITE) != WAIT_OBJECT_0);
GetExitCodeProcess(hProcess, &ret);
//如果ret!=0,异常退出；
//
CloseHandle(hPipeOutputWrite);
while (true)
{
bTest = ReadFile(
hPipeOutputRead, // handle of the read end of our pipe
&szBuffer, // address of buffer that receives data
sizeof(szBuffer), // number of bytes to read
&dwNumberOfBytesRead, // address of number of bytes read
NULL // non-overlapped.
);
if (!bTest)
{
break;
}
// do something with data.
szBuffer[dwNumberOfBytesRead] = 0; // null terminate
}
if (!ret)
{
printf("123%s456\nbtest:%d\n", szBuffer, bTest);
CloseHandle(hProcess);
CloseHandle(hPipeOutputRead);
break;
}
}
}
//std::cout << "Hello World!\n";
system("pause");
}