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POredirecting stdout to pipe write end
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copied!<p>I'm writing a little program, and here is what it should do.</p> <p>In the main process I have to create a new one and that one should execute another program which only does a printf("text"). I want to redirect the pipe write end on stdout and the main process should read from its pipe read and and print it on stdout. I wrote the code but again and again I get a segmentation fault when the parent process tries to read from the pipe.</p> <pre><code>#include <sys/types.h> #include <stdio.h> #include <string.h> #include <unistd.h> #include <stdlib.h> void write_to(FILE *f){ char buf[50]; fprintf(f,"KOMA"); } int main(){ int cpPipe[2]; int child1_fd; int child2_fd; if(pipe(cpPipe) == -1){ fprintf(stderr,"ERROR PIPE creation"); exit(1); }else{printf("pipe couldn't be created\n");} child1_fd = fork(); if(child1_fd < 0){ fprintf(stderr, " CHILD creation error"); exit(1); } if(child1_fd == 0){ printf("*CHILD*\n"); char program[] = "./Damn"; int dupK; printf("stdout %d \n", STDOUT_FILENO); printf("stdin %d \n", STDIN_FILENO); printf("pipe1 %d \n", cpPipe[1]); printf("pipe0 %d \n", cpPipe[0]); // closing pipe write close(cpPipe[0]); close(1); dup(cpPipe[1]); printf("and"); close(cpPipe[1]); exit(0); }else{ printf("*Parent*\n"); char *p; char *buf; FILE *pipe_read; close(cpPipe[1]); pipe_read = fdopen(cpPipe[0],"r"); while((buf = fgets(p,30,pipe_read)) != NULL){ printf("buf %s \n", buf); } wait(); printf("Child is done\n"); fclose(pipe_read); exit(0); } } </code></pre> <p>Do I have to close the pipe write end when I redirect stdout to it?</p>

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