如何用C/C++获得冲制台程序打印的字符串

[hyq1986]

写C/C++程序，如何才能在调用外部控制台程序的同时获得这些程序的用户返回信息？

如给一个控制台程序做GUI辅助程序

谢谢！

[boxban]

Keywords: _pipe, _spawnvp, _dup2
Example 2

// This is a simple filter application. It will spawn
// the application on command line. But before spawning
// the application, it will create a pipe that will direct the
// spawned application's stdout to the filter. The filter
// will remove ASCII 7 (beep) characters.

// Beeper.Cpp

/* Compile options needed: None */
#include <stdio.h>
#include <string.h>

int main()
{
int i;
for(i=0;i<100;++i)
{
printf("\nThis is speaker beep number %d... \n\7", i+1);
}
return 0;
}


// BeepFilter.Cpp
/* Compile options needed: none
Execute as: BeepFilter.exe <path>Beeper.exe
*/
#include <windows.h>
#include <process.h>
#include <memory.h>
#include <string.h>
#include <stdio.h>
#include <fcntl.h>
#include <io.h>

#define OUT_BUFF_SIZE 512
#define READ_HANDLE 0
#define WRITE_HANDLE 1
#define BEEP_CHAR 7

char szBuffer[OUT_BUFF_SIZE];

int Filter(char* szBuff, ULONG nSize, int nChar)
{
char* szPos = szBuff + nSize -1;
char* szEnd = szPos;
int nRet = nSize;

while (szPos > szBuff)
{
if (*szPos == nChar)
{
memmove(szPos, szPos+1, szEnd - szPos);
--nRet;
}
--szPos;
}
return nRet;
}

int main(int argc, char** argv)
{
int nExitCode = STILL_ACTIVE;
if (argc >= 2)
{
HANDLE hProcess;
int hStdOut;
int hStdOutPipe[2];

// Create the pipe
if(_pipe(hStdOutPipe, 512, O_BINARY | O_NOINHERIT) == -1)
return 1;

// Duplicate stdout handle (next line will close original)
hStdOut = _dup(_fileno(stdout));

// Duplicate write end of pipe to stdout handle
if(_dup2(hStdOutPipe[WRITE_HANDLE], _fileno(stdout)) != 0)
return 2;

// Close original write end of pipe
close(hStdOutPipe[WRITE_HANDLE]);

// Spawn process
hProcess = (HANDLE)spawnvp(P_NOWAIT, argv[1],
(const char* const*)&argv[1]);

// Duplicate copy of original stdout back into stdout
if(_dup2(hStdOut, _fileno(stdout)) != 0)
return 3;

// Close duplicate copy of original stdout
close(hStdOut);

if(hProcess)
{
int nOutRead;
while (nExitCode == STILL_ACTIVE)
{
nOutRead = read(hStdOutPipe[READ_HANDLE],
szBuffer, OUT_BUFF_SIZE);
if(nOutRead)
{
nOutRead = Filter(szBuffer, nOutRead, BEEP_CHAR);
fwrite(szBuffer, 1, nOutRead, stdout);
}

if(!GetExitCodeProcess(hProcess,(unsigned long*)&nExitCode))
return 4;
}
}
}

printf("\nPress \'ENTER\' key to continue... ");
getchar();
return nExitCode;
}

[hyq1986]

原来涉及进程间通讯