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POparent process, and a child process
 

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    <p>I am trying to write a program that The parent process will take the arguments to main() and send the characters in them one at a time to the child process through a pipe (one call to write for each character). The child process will count the characters sent to it by the parent process and print out the number of characters it received from the parent. The child process should not use the arguments to main() in any way whatsoever. The child should return normally and not have the parent kill the child.</p> <p>Am i counting the arguments right? am i sending the arguments in one at a time, and am i reaping the child? </p> <pre><code>#include &lt;sys/wait.h&gt; #include &lt;stdio.h&gt; #include &lt;stdlib.h&gt; #include &lt;unistd.h&gt; #include &lt;string.h&gt; #define size = 100; int main(int argc, char *argv[]) { int i, count =0; int c; int fdest[2]; // for pipe pid_t pid; //process IDs char buffer[BUFSIZ]; if (pipe(fdest) &lt; 0) /* attempt to create pipe */ perror( "pipe" ); if ((pid = fork()) &lt; 0) /* attempt to create child / parent process */ { perror( "fork" ); } /* parent process */ else if (pid &gt; 0) { close(fdest[0]); for (i=1; i &lt; argc; ++i) { for (c=0; c &lt; strlen(argv[i]); ++c) { write(fdest[1], &amp;argv[i][c], 1); } } close(fdest[1]); wait(NULL); exit(0); } else { /* child Process */ close(fdest[1]); while (read(fdest[0], &amp;buffer, 1) &gt; 0) { count++; } printf("\nchild: counted %d characters\n", count); } wait(NULL); exit(0); } </code></pre>
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    1. COIt looks like you've posted this question before. Perhaps you could explain what's different about this question from your previous one: http://stackoverflow.com/questions/2390868/passing-command-line-arguments-to-a-child-process-and-count-them
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      1. USGreg Hewgill
    2. COThe main difference seems to be the strictures about writing one character at a time to the pipe, and reading one character at a time from the pipe.
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      1. USJonathan Leffler
    3. CONeeds homework tag ?
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      1. USPaul R
 

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