Shell Programming and Scripting

Hello All,

I was wondering how to capture the output of an "interactive" command that is run...? I think "interactive" is the
word I'm looking for. For example, commands like "top" and "iftop"...

The One I'm trying to work with is "iftop". When you run "iftop" from the command line it begins a screen in the
terminal that shows the ethernet interfaces and their kbps, Tx, Rx, etc... I know "top" has an option that instead of top
updating the screen once every so many seconds it outputs one screen and the command exits.

I didn't see any Options like that for "iftop" though.

After you run the command, then hit Control-C/or 'Q' to exit the command it shows the following on the screen:

Code:

interface: eth0
IP address is: 192.168.5.101
MAC address is: 55:55:**:**:**:**

Is there anyway to capture that output (above)...?
I tried the usual way, and also tried redirecting stderr to stdout but it still didn't have anything in the variable after
it completed the command.

Here's what I tried that hasn't worked yet: (tried each one below, and not all at the same time obviously...)

Code:

iftop_OUTPUT=$(iftop)
iftop_OUTPUT=$(iftop 2>&1)
echo -ne "$iftop_OUTPUT\n"

# Also tried printing to a file...
iftop &> /print/to/output/file/iftop_output.txt
iftop_OUTPUT=$(cat /print/to/output/file/iftop_output.txt)

I thought that since just setting the command to a variable, and since that variable was empty when I 'echoed' it, that it was
actually printing that to stderr but that hadn't worked either...

Anyone know if this is possible?
Any thoughts would be much appreciated!


Thanks in Advance,
Matt

---------- Post updated at 04:52 PM ---------- Previous update was at 04:38 PM ----------

**UPDATE: *Good News!!!
----------------------------------------------------------------------------------

So playing around a bit more with this I just tried using the "tee"command. This seemed to actually save some data from the command
but it mostly looked like jibberish...

Also, I couldn't just run the iftop command and either redirect or using tee and have the command just stop so I tried adding "pkill" in there
to stop the command right away since I didn't know the PID.

Here's the command I just tried:

Code:

iftop 2>&1 | tee ./myOutput.txt | pkill iftop

And here is the contents of "myOutput.txt" File:

Code:

interface: eth1
IP address is: 192.168.5.101
MAC address is: 55:**:**:**:**:**
^[[?1049h^[[1;24r^[(B^[[m^[[4l^[[?7h^[[?1h^[=

The Output is good enough for what I need to do. But I just wanted to ask and make sure that doing it this
way wouldn't run into a problem at anytime...?

Thanks,
Matt

Look at the col command and this link shows how to pipe the tee output through sed to remove control codes:
exec - bash tee remove color - Stack Overflow

Hey spacebar, thanks for the reply!

Cool thanks, I'll check that link out...
Luckily, I just recently had to do the same thing (i.e. removing the control codes), so I should be ok there...

Thanks Again,
Matt