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    <p>The code provided by eerpini does not work as written. Note, for example, that the pipe ends that are closed in the parent are used afterwards. Look at </p> <pre><code>close(wpipefd[1]); </code></pre> <p>and the subsequent write to that closed descriptor. This is just transposition, but it shows this code has never been used. Below is a version that I have tested. Unfortunately, I changed the code style, so this was not accepted as an edit of eerpini's code. </p> <p>The only structural change is that I only redirect the I/O in the child (note the dup2 calls are only in the child path.) This is very important, because otherwise the parent's I/O gets messed up. Thanks to eerpini for the initial answer, which I used in developing this one.</p> <pre><code>#include &lt;stdio.h&gt; #include &lt;stdlib.h&gt; #include &lt;unistd.h&gt; #include &lt;errno.h&gt; #define PIPE_READ 0 #define PIPE_WRITE 1 int createChild(const char* szCommand, char* const aArguments[], char* const aEnvironment[], const char* szMessage) { int aStdinPipe[2]; int aStdoutPipe[2]; int nChild; char nChar; int nResult; if (pipe(aStdinPipe) &lt; 0) { perror("allocating pipe for child input redirect"); return -1; } if (pipe(aStdoutPipe) &lt; 0) { close(aStdinPipe[PIPE_READ]); close(aStdinPipe[PIPE_WRITE]); perror("allocating pipe for child output redirect"); return -1; } nChild = fork(); if (0 == nChild) { // child continues here // redirect stdin if (dup2(aStdinPipe[PIPE_READ], STDIN_FILENO) == -1) { exit(errno); } // redirect stdout if (dup2(aStdoutPipe[PIPE_WRITE], STDOUT_FILENO) == -1) { exit(errno); } // redirect stderr if (dup2(aStdoutPipe[PIPE_WRITE], STDERR_FILENO) == -1) { exit(errno); } // all these are for use by parent only close(aStdinPipe[PIPE_READ]); close(aStdinPipe[PIPE_WRITE]); close(aStdoutPipe[PIPE_READ]); close(aStdoutPipe[PIPE_WRITE]); // run child process image // replace this with any exec* function find easier to use ("man exec") nResult = execve(szCommand, aArguments, aEnvironment); // if we get here at all, an error occurred, but we are in the child // process, so just exit exit(nResult); } else if (nChild &gt; 0) { // parent continues here // close unused file descriptors, these are for child only close(aStdinPipe[PIPE_READ]); close(aStdoutPipe[PIPE_WRITE]); // Include error check here if (NULL != szMessage) { write(aStdinPipe[PIPE_WRITE], szMessage, strlen(szMessage)); } // Just a char by char read here, you can change it accordingly while (read(aStdoutPipe[PIPE_READ], &amp;nChar, 1) == 1) { write(STDOUT_FILENO, &amp;nChar, 1); } // done with these in this example program, you would normally keep these // open of course as long as you want to talk to the child close(aStdinPipe[PIPE_WRITE]); close(aStdoutPipe[PIPE_READ]); } else { // failed to create child close(aStdinPipe[PIPE_READ]); close(aStdinPipe[PIPE_WRITE]); close(aStdoutPipe[PIPE_READ]); close(aStdoutPipe[PIPE_WRITE]); } return nChild; } </code></pre>
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