c++ - Why does this code stop running when it hits the pipe? -

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When this program is run then the parent goes through the loop, then when he writes the pipe The child switches.

Parents 4741 14087 (only 5 lines are expected)

Expected production (with randomly generated numbers):

Parents 4741 14087

Child 4740 47082

Parents 4741 11345

Children 4740 99017

Parents 4741 96744 < / P>

Hair 4740 98653 (when Variable 3 is given and the final number is a randomly generated number) 

  #include & lt; Stdio.h & gt; # Include & lt; Iostream & gt; # Include & lt; Unistd.h & gt; # Include & lt; Sys / types.h & gt; # Include & lt; Unistd.h & gt; # Include & lt; Stdlib.h & gt; # Include & lt; Time.h> # Include & lt; Ctime & gt; using namespace std; Int main (int argc, char * argv []) {int pid = fork (), temp, randNum, count, pipeName [2], pipeName2 [2]; String converter; Pipes (pipeName); Conver = azr [1]; Temp = atoi (conver.c_str ()); Four letters; If (pid == 0) {// Child srand ((unsigned) time (zero) * getpid ()); // Close off unused pipe (pipeline 2 [1]); Close (pipeName [0]); // To switch for input loop (int i = 0; i   
 The program ends when the child reads from the pipeline in the child.   
 
 
 your main mistake  fork ()  before starting the pipe Both the parents and the child have their own personal (not shared through FD inheritance) pipe pair  pipeName , and only parents start with the pipe FD  PipeName2 .  
 For parents, there is no data to read behind  pipe-names [0] . For the child ... who knows what the FD is writing?  pipeName2 [1] ? If you are lucky that fail with EBADF.  
 Then, first  pipes ()  twice, and  then   fork () , and see if things improve it happens.

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