Bash passing information from script to script

Question

I have a bash CGI logging connections to my server, I want to that when a new connection is requested/stablised/served this script passes an argument/variable to another script running in the background? is this possible? how can i do this?

I have tried environmental variables but this will only work in the same shell and I cannot be sure both will be running on the same shell. I've tried writing to a file but how could i know when the file has been edited thus allow the second script to execute the command.

I'm starting to get crazy, this must be possible I cannot believe to "programs" cannot share information... :O

maybe i'm taking the wrong approach, can someone please advise?

Thanks, Marco P.

Answer 1

named pipes might be one way, although it is blocking:

setup:

mkfifo /path/to/named/pipe

cgi script:

echo "some data" > /path/to/named/pipe   # blocks until other script consumes!

background script:

while :; do
    read data < /path/to/named/pipe      # blocks until cgi script produces!
    do_stuff_with "$data"
done