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POAfter fork, do the parent and child process share the file descriptor created by pipe?
 

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    <pre><code>int main() { int data_processed; int file_pipes[2]; const char some_data[] = "123"; char buffer[BUFSIZ + 1]; pid_t fork_result; memset(buffer, '\0', sizeof(buffer)); if (pipe(file_pipes) == 0) { fork_result = fork(); if (fork_result == -1) { fprintf(stderr, "Fork failure"); exit(EXIT_FAILURE); } // We've made sure the fork worked, so if fork_result equals zero, we're in the child process. if (fork_result == 0) { data_processed = read(file_pipes[0], buffer, BUFSIZ); printf("Read %d bytes: %s\n", data_processed, buffer); exit(EXIT_SUCCESS); } // Otherwise, we must be the parent process. else { data_processed = write(file_pipes[1], some_data, strlen(some_data)); printf("Wrote %d bytes\n", data_processed); } } exit(EXIT_SUCCESS); } </code></pre> <p>Based on my understanding, the child process created by fork doesn't share variables with its parent process. Then, why here the parent can write to one file descriptor and child process can get the data by reading from another file descriptor. Is this because they are controled somehow by the pipe function internally?</p>
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