pipe-lost.sh

#!/usr/bin/env bash

set -e

pipe=test.pipe
lines=2

mount -o size=100M -t tmpfs tmpfs /tmp
cd /tmp

gcc -xc - <<-IFH
#include <stdio.h>
#include <stdlib.h>

int main(int argc, char **argv)
{
        int num = atoi(argv[1]);
        int i;
        for (i = 0; i < num; ++i) {
                if (write(STDOUT_FILENO, "\n", 1) != 1) {
                        fprintf(stderr, "Write failed\n");
                        return 1;
                }
        }
        fprintf(stderr, "Write success (%i)\n", num);
        return 0;
}
IFH

function writeToPipe()
{
        echo "Writing to pipe $1 ($lines lines)"

        ./a.out $lines
}
function readFromPipe()
{
        echo "Reading from pipe $1 ($lines lines)"

        local l=0
        while [[ ! $l -eq $lines ]]; do
                readed=$(wc -l "$1" | awk '{print $1}')
                let l+=$readed

                echo "Readed $readed lines"
        done

        echo "Finished reading"
}

export -f readFromPipe writeToPipe
export lines

# XXX: group to allow fast-copying
rm -f $pipe && mkfifo $pipe && timeout -s TERM 5s xargs -P2 -I{} bash -c '{}' <<-IFH
        readFromPipe $pipe
        sleep 1 && writeToPipe $pipe
IFH

#
# After this seq of commands it can loose one record,
# and will be killed by timeout
# And it can reproduced only using shell-buildin, and this is pretty obvious,
# because it must be _faster_ then read, while with execve(2) it won't be.
#