Hello- Great site, thanks for the help... :)

Anyway, I am in the process of writing a Perl script to create a pipe, read a file list, and pass each file name in the list to the pipe with some selectable delay between sending the file names to the pipe. Another program is called which is set up to read and open the filenames from the pipe and then do some processing on the file it opens. Everything works great if I manually create the pipe by:

$ mknod named.pipe p
$ cat >> named.pipe

and enter the filenames into the pipe by typing the name in the terminal followed by a carriage return, but I can't figure out why this script below isn't doing the job.

It happens that the first file name is put in the pipe, then it is put in immediately again, then the program to read the pipe dies without any error given. Here is the relevant code snippet:

#!/usr/bin/perl -w

# Set parameters here
$obs_file_dir = "/some/path/";
$wait_time = 30;

# Read observed file names to array
$obs_file_list = $obs_file_dir . "file_list.txt";
open(DIR, $obs_file_list) || die("Could not open file!");
@obs_files = <DIR>;
close(DIR);

# Start program to read pipe and process data
system("otherProgramToReadPipe");

# Open pipe
system("mknod named.pipe p");

foreach $file (@obs_files)
{
open(FIFO, ">> named.pipe");
print FIFO $obs_file_dir . $file;
close(FIFO);
sleep $wait_time;
}

close(FIFO);

Thank you for your thoughts!

In reply to Problem with FIFO by pktrain

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