Use awk to compare values piped from df

[osmosys8]

I want to use awk to compare values piped from "df" like so:

df:

Filesystem     1K-blocks      Used Available Use% Mounted on
/dev/sda1      725649232 118249576 571080120  18% /
udev             2994044         4   [COLOR=#EF2929]2994040[/color]   1% /dev
tmpfs            1201132      1120   [COLOR=#EF2929]1200012[/color]   1% /run
none                5120         0      5120   0% /run/lock
none             3002824       352   3002472   1% /run/shm
/dev/sr0         5487686   5487686         0 100% /media/UDF Volume

Then pull out the red values:

2994040
1200012

And run a comparison:

if 2994040 > 1200012 then:
echo "udev exceeds tmpfs in size"
else echo "udev is smaller than tmpfs in size"
fi

Something like that. I've gotten this far:

#!/bin/sh
 awk '{print $c}' c=${1:-2}

I put the above into "colmn" and then ran:

df | ./column which outputs:

1K-blocks
725649232
2994044
1201132
5120
3002824
5487686

I don't know how to grab the values I want, and I don't want to use cut. I want it to be smart enough to read the lines that go with udev or tmpfs (or whatever lines I specify). I imagine that if I can grab the values then I can store them in variables somehow and then run some comparison logic, but I don't know how to put it all together.

Thanks!

 

[feherke]

Hi

df | awk '[navy]$1[/navy][teal]==[/teal][green][i]"udev"[/i][/green][teal]||[/teal][navy]$1[/navy][teal]==[/teal][green][i]"tmpfs"[/i][/green][teal]{[/teal]s[teal][[/teal][navy]$1[/navy][teal]]+=[/teal][navy]$4[/navy][teal]}[/teal]END[teal]{[/teal][COLOR=chocolate]printf[/color][green][i]"udev %s tmpfs in size"[/i][/green][teal],([/teal]s[teal][[/teal][green][i]"udev"[/i][/green][teal]]>[/teal]s[teal][[/teal][green][i]"tmpfs"[/i][/green][teal]])?[/teal][green][i]"exceeds"[/i][/green][teal]:[/teal][green][i]"is smaller than"[/i][/green][teal]}[/teal]'

Tested with [tt]gawk[/tt] and [tt]mawk[/tt].

Note that on my machine there are 7 tmpfs entries in [tt]df[/tt]'s output, so I put my code to add them and compare the sums.

Feherke.
[link feherke.github.com/]

http://feherke.github.com/

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