Hello everyone, first this is a fanastic website. I really like it. Now to my problem. I have a linux terminal program which waits for user input a.k.a. a user to press the return key to get back to the terminal prompt again. So basically I want to parse the stdout off that program ( i need information about the parameters). So I made the following: 
my $parameter_output = `echo "\n" |programname -help`;

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and this works perfectally well for me, the program terminates, the complete stdout is stored in that variable and my perl script moves on... But I thought to me..."hey all this commandline statement above is doing is forking a process and putting that newline character from the stdout from process 1 (parent) to stdin from the second process(child)". So I tried to reproduce this with fork but I cannot find the reason why this does not work. small snippet.... 
pipe (IN,OUT);
my $pid = fork ();
die("fork failed") if (!defined($pid));
if ($pid == 0 ) {
#the child
exec ('programname -help');

}
else {
    #parent
    sleep (2);
#printing the newline character in the child process
    print OUT "\n";
    waitpid ($pid,0);

 
}

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I also tried this with signals.... snippet: 
sub print_it {print "\n"};
my $SIG{INT}=\&print_it;
....
else {
    #parent
    sleep (2);
    kill INT=>$pid;
    waitpid ($pid,0);

 
}

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neither this works.... I think somewhere I have a big error in reasoning I think. So it would be very kind if someone could help me. Thanks in advance joshi

In reply to Trying to pass a "press any key" program in terminal. by joschka

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