[CentOS] CentOS 7 bash perhaps off topic

Mon Nov 26 20:46:00 UTC 2018
Leroy Tennison <leroy at datavoiceint.com>

If I'm understanding you corectly, you want smwebsocket to continuously pull data passing it to grep for filtering and ultimately to myprogram to update a database.  If that's correct I haven't had an opportunity to work with that but my current understanding of how pipelining works is that smwebsocket would retrieve $URL (which would be a finite amount of data), it would end sending output to grep which would filter it (and end) sending its output to the while loop around myprogram which would process it until there was no more data (and end) thus landing at 'sleep 60' only to start over again.  If a pipeline is capable of continuous processing I'm not aware of it (but would be glad to know that's how it can work).

Leroy Tennison
Network Information/Cyber Security Specialist
E: leroy at datavoiceint.com
2220 Bush Dr
McKinney, Texas
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From: CentOS <centos-bounces at centos.org> on behalf of Jerry Geis <jerry.geis at gmail.com>
Sent: Monday, November 26, 2018 2:11 PM
To: CentOS mailing list
Subject: [EXTERNAL] [CentOS] CentOS 7 bash perhaps off topic

hi all,

I have a small script that seems to be exiting and hitting the sleep 60...
The smwebsocket just connects to the web socket provided and outputs the
data. This works manually.

the myprogram just opens a database and writes the line...

My desire is to run the smwebsocket, connect to the websocket and output
the data (line by line) when we get a line that matches Location take that
line and output to the database. Seems simple. I desire this to keep the
connection alive and just continue to read data and grep on the data etc...
if smwebsocket does exit, sleep 60 and reconnect.

However it seems to be exiting and running the sleep 60. Am I missing
something ?

while [ 1 ]
                        smwebsocket "$URL" | grep Location | while read line
                                myprogram -data "$line"

                sleep 60

All the pieces work - just not the actual running.  What am I missing?

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