How to get specific results from 'free -m' ?

[ITSMERSH]

Hi.

I need to get some specific results from 'free -m' into a variable.

total used free shared buffers
Mem: 3987 1490 2497 0 3
-/+ buffers: 1486 2501
Swap: 9039 99 8940

I need those values marked bold - which is total memory / free memory.

Is there a simple and/or easy way to achieve?

Thanks

Edit:

After a some time of try and fail I could achieve it that way:

FREERESULT="`free -m`"
TOTAL=$(echo $FREERESULT|cut -d':' -f2|cut -d' ' -f2)
FREE=$(echo $FREERESULT|cut -d':' -f2|cut -d' ' -f4)

Since there's two more lines including ':', is this secure?

Is there something smarter, a one liner probably?

[MochiMoppel]

Is there something smarter, a one liner probably?

Isn't your solution smart enough? Sure you could assign 2 variables in one line, but the result would look ugly.

Another way:

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FREERESULT=(`free -m`)
TOTAL=${FREERESULT[6]}
FREE=${FREERESULT[8]}

[01micko]

You can make a one-liner with read (and grep). Note that using read like this is a bashism.

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# read a b c d e f g <<<$(free -m|grep '^Mem')
# echo $b $d

[MochiMoppel]

grepless:

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read x x x x x x TOTAL x FREE x <<< $(free -m)

[fredx181]

Another way:
Code:
FREERESULT=(`free -m`)
TOTAL=${FREERESULT[6]}
FREE=${FREERESULT[8]}

That doesn't work with newer version

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# free --version
free from procps-ng 3.3.12

Output is different from older:

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# free -m
              total        used        free      shared  buff/cache   available
Mem:           2011         301         852         114         857        1376
Swap:          3184           0        3184

Fred

[musher0]

Hello *RSH.

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free -m | awk '$1 ~ /Mem/ { print $2,$4 }'

This way you get only the desired results.
You can change the , to "\t" if you wish the line to "breathe" more.

Examples:

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free -m | awk '$1 ~ /Mem/ { print $2,$4 }'
3914 2630

free -m | awk '$1 ~ /Mem/ { print $2"\t"$4 }'
3914	2593

Awk is totally secure, BTW. Unused data is discarded to /dev/null, as I
understand it.

IHTH

[MochiMoppel]

That doesn't work with newer version

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# free --version
free from procps-ng 3.3.12

In my puppy free is linked to busybox

This should work in any version:

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FREERESULT=(`free -m|grep Mem:`)
TOTAL=${FREERESULT[1]}
FREE=${FREERESULT[3]}

.

[musher0]

To make it a bit more informative:

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echo -e "total\tfree";free -m | awk '$1 ~ /Mem/ { print $2"\t"$4 }'
total	free
3914	2568

[fredx181]

In my puppy free is linked to busybox

Ah, yes, probably the case in all puppies, so my post above can be ignored.

[MochiMoppel]

Ah, yes, probably the case in all puppies, so my post above can be ignored.

So probably my edit can be ignored too

[musher0]

Hi *RSH.

Careful, it's a memory clean-up script! It's not exactly what you are looking
for, but there may be some code you wish to plunder in here:
http://murga-linux.com/puppy/viewtopic. ... ost#831720

It's derived from Joe Arose's original, way back when, with add-ons /
suggestions from various forum members. It may save you some time,
who knows.

IHTH.

[ITSMERSH]

Wow, thanks for all the replies!

A lot to check out...

[rockedge]

MochiMoppel I took your code snip and using it as an icon on the desktop

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#!/bin/sh
FREERESULT=(`free -h|grep Mem:`)
TOTAL=${FREERESULT[1]}
FREE=${FREERESULT[3]}
gxmessage "Total->$TOTAL  Free->$FREE"

[musher0]

@*RSH: You're welcome!

[ITSMERSH]

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free -m | awk '$1 ~ /Mem/ { print $2,$4 }'

Today I was in the need to get specific results from --> uptime <-- to show some statistics in a gui. The output of --> uptime <-- varies dependent on how long the computer is running.

So I wrote a small line to get the desired information.

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UPTIME="`uptime | cut -d ' ' -f 4 | cut -d ',' -f 1` hours"

But after the computer was running for more than 24 hours this line returned just --> 1 <-- instead of e.g. 25:43.

So I was in the need to modify the above line of code.

Thanks to the coded line above by musher0 it seems I'm going to understand --> awk <-- at least a little. So, here's how I extracted that desired information when the computer is running for more than 24 hours.

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# Get up-time of running System
UPTIME="`uptime`"; echo "$UPTIME" > /tmp/upt;
if (grep 'day' /tmp/upt >/dev/null) then
	UPTIME1=`uptime | awk '$2 ~ /up/ { print $3,$4,$5 }' | cut -d ',' -f 1`
	UPTIME2=`uptime | awk '$2 ~ /up/ { print $3,$4,$5 }' | cut -d ',' -f 2`
	UPTIME="$UPTIME1, $UPTIME2 hours"
	else
	UPTIME="`uptime | cut -d ' ' -f 4 | cut -d ',' -f 1` hours"
fi

Of course, I'm sure there's some smarter solution by the experts here. Though, I'm somehow glad to have understood a bit more of those special functions.

Thank you, musher0 !

[musher0]

Hello Rainer.

My pleasure!

But maybe you would prefer this format:

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uptime | awk '{ print $3,$4,$5}' | awk -F"," '{ print $1","$2}'

It will output something like:

5 days, 19:56

Or this:

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Minutes="`uptime | awk -F"," '{ print $2 }' | awk -F":" '{ print $2 }'`";Hours="`uptime | awk '{ print ($3*24)+$5}'`";echo "Uptime: $Hours h $Minutes m"

It will output something like:

Uptime: 140 h 32 m

Depending on your needs of course.

I mention it because "awk purists" try not to use awk and cut on the same
line. We simply repeat an awk command to fish out the desired data.

And as you say, I am far from being an awk expert, although I have some
experience with it. I am sure someone can come up with better awk code
for your need.

Have fun!

[ITSMERSH]

MochiMoppel I took your code snip and using it as an icon on the desktop

#!/bin/sh
FREERESULT=(`free -h|grep Mem:`)
TOTAL=${FREERESULT[1]}
FREE=${FREERESULT[3]}
gxmessage "Total->$TOTAL Free->$FREE"

I needed to change the -h to -m to get this to work from script.

Thanks @musher0.

I'm sure I will play a little with all of that next...

[MochiMoppel]

You should be aware that (most?) Puppies use the busybox version of uptime.

On 2 of my machines uptime produced these outputs:

• 11:12:04 up 17 min, load average: 0.00, 0.02, 0.04
  11:13:56 up 29 days, 43 min, load average: 0.16, 0.26, 0.27

None of the proposed awk solutions would work.

[ITSMERSH]

Here is mine:

04:16:02 up 2 days, 58 min, load average: 0.35, 0.41, 0.47

It seems I need to do a 3rd modification in case there's only minutes and no hours.

[MochiMoppel]

So I wrote a small line to get the desired information.

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UPTIME="`uptime | cut -d ' ' -f 4 | cut -d ',' -f 1` hours"

Here is mine:
04:16:02 up 2 days, 58 min, load average: 0.35, 0.41, 0.47

If this is yours, your small line produces days hours

My computer is now running for more than an hour and less than a day, my uptime produces
17:24:36 up 5:17, load average: 0.00, 0.03, 0.05
and your code returns load hours

I wonder if using the uptime command is the right approach. You may want to consider to read the /proc/uptime value directly.