Hi Monks,

I have 3 programs. 1 perl script and a java program which are the same. Another main perl script which uses one of the above. The main perl script is shown below. 

open(sense,"java Listen -port /dev/ttyUSB0:115200 |")|| die "Failed to
+ listen";
while(<sense>)
{
    $currentline= $_;
    print ("Line $currentline");   
}

[download]

This works fine. Now the second perl script, I had written on my own. I am printing the data collected over the serial port with 

print stdout "$data";

[download]
This also works fine standalone. But when I replace the java and put the new script on the main (as shown below), it doesn't work. The output is delayed and comes with around 20 lines of data at once. 

open(sense,"./read_serial.pl |")|| die "Failed to listen";

[download]
I also tried running 
system ("./read_serial &");
open(sense,">- |") || die "Failed to listen";

[download]
I am not sure if the last one is correct or not. I think I should be reading the STDIN, but when I put "-" it dies off. Any help is appreciated. Thanks Thanks

In reply to Pipe Input delayed by yodha

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