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exec -a $NAME $COMMAND $ARGS
`your_cmd -erase_all_files` is the real process, but harmless-looking getty appears in the process table.
Never actually had a need to do this, but interesting nonetheless... Tested in bash, dash.
-a $NAME
"pass NAME as the zeroth argument to COMMAND", i.e. customise the name of the process (as commonly seen with `ps`)
Good for finding outdated timthumb.php scripts which need to be updated, anything over 2.0 should be secure, below that timthimb is vulnerable and can be used to compromise your website.
While going through the source code for the well known ps command, I read about some interesting things.. Namely, that there are a bunch of different fields that ps can try and enumerate for you. These are fields I was not able to find in the man pages, documentation, only in the source.
Here is a longer function that goes through each of the formats recognized by the ps on your machine, executes it, and then prompts you whether you would like to add it or not. Adding it simply adds it to an array that is then printed when you ctrl-c or at the end of the function run. This lets you save your favorite ones and then see the command to put in your .bash_profile like mine at : http://www.askapache.com/linux-unix/bash_profile-functions-advanced-shell.html
Note that I had to do the exec method below in order to pause with read.
t ()
{
local r l a P f=/tmp/ps c='command ps wwo pid:6,user:8,vsize:8,comm:20' IFS=' ';
trap 'exec 66
exec 66 $f && command ps L | tr -s ' ' >&$f;
while read -u66 l >&/dev/null; do
a=${l/% */};
$c,$a k -${a//%/} -A;
yn "Add $a" && P[$SECONDS]=$a;
done
}
You have a script where =ALL= STDERR should be redirected to STDIN and you don't want to add "2>&1" at the end of each command...
E.G.:
ls -al /foo/bar 2>&1
Than just add this piece of code at the beginning of your script!
I hope this can help someone. :)
Please be careful while executing the following command as you don?t want
to delete the files by mistake. The best practice is to execute the same
command with ls ?l to make sure you know which files will get deleted when
you execute the command with rm.
pings a server once per second, and beeps when the server is unreachable.
Basically the opposite of:
ping -a server-or-ip.com
which would beep when a server IS reachable.
You could also substitute beep with any command, which makes this a powerful alternative to ping -a:
while true; do [ "$(ping -c1W1w1 server-or-ip.com 2>/dev/null | awk '/received/ {print $4}')" = 1 ] && date || echo 'server is down!'; sleep 1; done
which would output the date and time every sec until the ping failed, in which case it would echo.
Notes:
Requires beep package.
May need to run as root (beep uses the system speaker)
Tested on Ubuntu which doesn't have beep out of the box...
sudo apt-get install beep