CreatePipe()等函数创建管道来操纵控制台

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#include <stdio.h>

#include <windows.h>

#define BUFSIZE 4096

HANDLE hChildStdinRd, hChildStdinWr, hChildStdinWrDup,

hChildStdoutRd, hChildStdoutWr, hChildStdoutRdDup,

hInputFile, hStdout;

BOOL CreateChildProcess( VOID );

VOID WriteToPipe( VOID );

VOID ReadFromPipe( VOID );

VOID ErrorExit( LPTSTR );

VOID ErrMsg( LPTSTR , BOOL );

DWORD main( int argc, char *argv[])

{

SECURITY_ATTRIBUTES saAttr;

BOOL fSuccess;

// Set the bInheritHandle flag so pipe handles are inherited.

saAttr.nLength = sizeof (SECURITY_ATTRIBUTES);

saAttr.bInheritHandle = TRUE;

saAttr.lpSecurityDescriptor = NULL;

// Get the handle to the current STDOUT.

hStdout = GetStdHandle(STD_OUTPUT_HANDLE);

// Create a pipe for the child process's STDOUT.

if (! CreatePipe(&hChildStdoutRd, &hChildStdoutWr, &saAttr, 0))

ErrorExit( "Stdout pipe creation failed\n" );

// Create noninheritable read handle and close the inheritable read

// handle.

fSuccess = DuplicateHandle(GetCurrentProcess(), hChildStdoutRd,

GetCurrentProcess(), &hChildStdoutRdDup , 0,

FALSE,

DUPLICATE_SAME_ACCESS);

if ( !fSuccess )

ErrorExit( "DuplicateHandle failed" );

CloseHandle(hChildStdoutRd);

// Create a pipe for the child process's STDIN.

if (! CreatePipe(&hChildStdinRd, &hChildStdinWr, &saAttr, 0))

ErrorExit( "Stdin pipe creation failed\n" );

// Duplicate the write handle to the pipe so it is not inherited.

fSuccess = DuplicateHandle(GetCurrentProcess(), hChildStdinWr,

GetCurrentProcess(), &hChildStdinWrDup, 0,

FALSE, // not inherited

DUPLICATE_SAME_ACCESS);

if (! fSuccess)

ErrorExit( "DuplicateHandle failed" );

CloseHandle(hChildStdinWr);

// Now create the child process.

fSuccess = CreateChildProcess();

if (! fSuccess)

ErrorExit( "Create process failed" );

// Get a handle to the parent's input file.

if (argc == 1)

ErrorExit( "Please specify an input file" );

hInputFile = CreateFile(argv[1], GENERIC_READ, 0, NULL,

OPEN_EXISTING, FILE_ATTRIBUTE_READONLY, NULL);

if (hInputFile == INVALID_HANDLE_VALUE)

ErrorExit( "CreateFile failed\n" );

// Write to pipe that is the standard input for a child process.

WriteToPipe();

// Read from pipe that is the standard output for child process.

ReadFromPipe();

return 0;

}

BOOL CreateChildProcess()

{

PROCESS_INFORMATION piProcInfo;

STARTUPINFO siStartInfo;

BOOL bFuncRetn = FALSE;

// Set up members of the PROCESS_INFORMATION structure.

ZeroMemory( &piProcInfo, sizeof (PROCESS_INFORMATION) );

// Set up members of the STARTUPINFO structure.

ZeroMemory( &siStartInfo, sizeof (STARTUPINFO) );

siStartInfo.cb = sizeof (STARTUPINFO);

siStartInfo.hStdError = hChildStdoutWr;

siStartInfo.hStdOutput = hChildStdoutWr;

siStartInfo.hStdInput = hChildStdinRd;

siStartInfo.dwFlags |= STARTF_USESTDHANDLES;

// Create the child process.

bFuncRetn = CreateProcess(NULL,

"child" , // command line

NULL, // process security attributes

NULL, // primary thread security attributes

TRUE, // handles are inherited

0, // creation flags

NULL, // use parent's environment

NULL, // use parent's current directory

&siStartInfo, // STARTUPINFO pointer

&piProcInfo); // receives PROCESS_INFORMATION

if (bFuncRetn == 0)

ErrorExit( "CreateProcess failed" );

else

{

CloseHandle(piProcInfo.hProcess);

CloseHandle(piProcInfo.hThread);

return bFuncRetn;

}

}

VOID WriteToPipe( VOID )

{

DWORD dwRead, dwWritten;

CHAR chBuf[BUFSIZE];

// Read from a file and write its contents to a pipe.

for (;;)

{

if (! ReadFile(hInputFile, chBuf, BUFSIZE, &dwRead, NULL) ||

dwRead == 0) break ;

if (! WriteFile(hChildStdinWrDup, chBuf, dwRead,

&dwWritten, NULL)) break ;

}

// Close the pipe handle so the child process stops reading.

if (! CloseHandle(hChildStdinWrDup))

ErrorExit( "Close pipe failed" );

}

VOID ReadFromPipe( VOID )

{

DWORD dwRead, dwWritten;

CHAR chBuf[BUFSIZE];

// Close the write end of the pipe before reading from the

// read end of the pipe.

if (!CloseHandle(hChildStdoutWr))

ErrorExit( "CloseHandle failed" );

// Read output from the child process, and write to parent's STDOUT.

for (;;)

{

if ( !ReadFile( hChildStdoutRdDup, chBuf, BUFSIZE, &dwRead,

NULL) || dwRead == 0) break ;

if (! WriteFile(hStdout, chBuf, dwRead, &dwWritten, NULL))

break ;

}

}

VOID ErrorExit ( LPTSTR lpszMessage)

{

fprintf (stderr, "%s\n" , lpszMessage);

ExitProcess(0);

}

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