[LCP]Fork freezes when forking more then one

[juman]

Hi,
I'm trying to write a software that will fork processes and control
their stdin/stdout. Forking just one process with a main looking like
everything works:

int main(void)
{
    prog *a;

    a = runthis ("/root/mp3/musidab/src/test.awk");
    write_to_child (a, "testa.mp3");
    stoprunning (a);
    sleep (5);

    return 0;
}

The sleep is only so I can check which processes is running.
But if I run 2 processes as can be seen in the real program the software
freezes when trying to read the output of the first process. Can somebody help
me with what I do wrong when trying to exit the forked process and read their
output?

--- The software start ---
#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>
#include <signal.h>
#include <string.h>

#define OK      0
#define FAIL    -1

#define STDIN   0
#define STDOUT  1
#define STDERR  2

#define INPUT   0
#define OUTPUT  1

#define CHILD   0
#define PARENT  1

typedef struct prog {
    int pid;
    int pc[2];
    int cp[2];
} prog;

void child (prog *run, char *runthis)
{
    close(STDOUT);
    dup( run->cp[OUTPUT]);
    close(STDIN);
    dup(run->pc[INPUT]);
    close(run->pc[OUTPUT]);
    close(run->cp[INPUT]);
    execlp (runthis, NULL);
    printf ("ERROR!\n");
    exit(1);
}

void write_to_child (prog *run, char *writethis)
{
    write (run->pc[OUTPUT], writethis, strlen (writethis));
}

prog *runthis (char *runthis)
{
    char ch;
    int outcount;
    prog *run;

    run = (prog *) malloc (sizeof (run));

    if( pipe(run->pc) < 0) {
        perror("Can't make pipe");
        exit(1);
    }
    if( pipe(run->cp) < 0) {
        perror("Can't make pipe");
        exit(1);
    }

    switch( run->pid = fork() ) {
        case FAIL:
                perror("Can't fork");
                exit(1);
        case CHILD:
                child (run, runthis);
        default:
                return run;
    }

    return run;
}

void stoprunning (prog *run)
{
    char ch;

    close(run->pc[OUTPUT]);
    close(run->cp[OUTPUT]);
    printf ("Closing!\n");
    while( read(run->cp[INPUT], &ch, 1) == 1)
        write(STDOUT, &ch, 1);
    printf ("Finished!\n");
}

int main(void)
{
    prog *a, *b;

    a = runthis ("/root/mp3/musidab/src/test.awk");
    b = runthis ("/root/mp3/musidab/src/test.awk");
    write_to_child (a, "testa.mp3");
    write_to_child (b, "testb.mp3");
    printf ("Running!\n");
    stoprunning (a);
    sleep (5);

    return 0;
}
--- The software end ---