What window is that?

Somtimes, in this wonderful Unix-Linux world, I want to know "what is the name of the executable application that popped open that window?" - this is especially helpful on user-friendly Linux distros that try to hide the gory details for the user. For example, what is the name of the application being used to open my PDF file by Nautilus here?







The answer is /usr/bin/evince, but it's not that easy to figure that out, now is it? The trick is to allow the window to open, then use... something... to identify the executable that opened it.

Some good folks came up with a neat answer over here which works pretty well. Use xprop to get the PID of the window, look up /proc/PID/exe and hey presto, you have the name of the executable (in most cases). I slightly adapted the second answer (I like shell aliases!) to come up with this addition to my Linux ~/.bashrc:

alias xident='ls -l /proc/$(xprop _NET_WM_PID | awk "{print \$NF}")/exe | awk "{print \$NF}"'

And for Solaris 10 and 11 we can do similar. There's no /proc/PID/exe, but pargs tells us the name of the executable. Note that this doesn't work in CDE, but does for Java Desktop/Gnome Desktop:

alias xident='pargs $(xprop _NET_WM_PID | awk "{print \$NF}") | awk "\$1 ~ /argv\[0\]/ {print \$2}"'

Word games

So The Age publishes a word game - Target - in the weekend paper. The rules are simple: you get 9 letters, and have to make as many words of 4 letters or more out of them, and there is one of the letters which must be included in all words. You also have to figure out what the original 9-letter word was which got scrambled up to provide the 9 letters. I quite like the challenge of making words out of the letters, but I rarely figure out the 9-letter word. It frustrates me. In fact, so much that I seem to spend more time figuring out ways to write a program to solve it for me. Yeah, really.

Anyway, I couldn't be bothered doing it "properly" so I decided to do a quick command-line hack to solve it. Today's quiz had the letters H K I A R T B R M Witness the following ugliness:

grep  '^.........$' /usr/share/dict/words|grep 'k'|grep 'r'|grep 'm'| grep 'h' |grep -E '[i]{1}'|grep -E '[a]+'|grep -v '[eou]'

There must be more elegant ways to achieve this, but still, it got the job done in a couple of minutes.

Oh, and the word was "birthmark" in case you wondered :-)

Edit: I solved this properly in perl today.

ldapsearch - exporting photos to named files

Simple requirement: export all staff photos from our LDAP repository. That bit is easy:

ldapsearch -h ldap -x -t -b "ou=People,dc=example,dc=com,dc=au"

But the files end up being called things like file:///tmp/ldapsearch-jpegPhoto-G4hm3V - not quite what we're after here. We want the pictures with the user ID as part of the name - e.g. pyarra.jpeg

After a bit of experimentation, I came up with this simple, elegant one-liner. OK, it's not all that simple, or elegant, but it is one-line. One long, ugly line:

ldapsearch -h ldap -t -x -b 'ou=People,dc=example,dc=com,dc=au'  uid | awk '$1 ~ /uid:/ {print $2}' | while read LUID; do ldapsearch -h ldap -t -x -b 'ou=People,dc=example,dc=com,dc=au' "uid=$LUID" jpegPhoto | (FILENAME=$(awk '$1 ~ /jpegPhoto:</ {print $2}' | sed -e 's/file:\/\///'); mv "$FILENAME" "/tmp/mugshots/$LUID.jpeg"); done

I probably should have bitten the bullet and done it as a Perl script. But that's the lure of the one-liner, eh? If I just go a little further, I'll have it!

Taming netstat with awk

Specifically, I want to see all network connections on a Solaris host which aren't localhost or from the local LAN. Let's start with netstat:

netstat -a -n -f inet -P tcp

Which gives me *everything*. Now let's filter out localhost connections:

netstat -a -n -f inet -P tcp | awk '$2 !~ /^127\.0\./'

Sweet! Now let's get rid of stuff on our local LAN (192.168.1.0/24) and stuff that's in a LISTEN state:

bash-3.00$ netstat -a -n -f inet -P tcp | \
awk '$2 !~ /^127\.0\./ && $2 !~ /^192\.168\.1\./ && $7 !~ /LISTEN/'

TCP: IPv4
   Local Address        Remote Address    Swind Send-Q Rwind Recv-Q    State
-------------------- -------------------- ----- ------ ----- ------ -----------
      *.*                  *.*                0      0 49152      0 IDLE
      *.*                  *.*                0      0 49152      0 IDLE
      *.1017               *.*                0      0 49152      0 BOUND
      *.32832              *.*                0      0 49152      0 BOUND
192.168.1.29.22      10.88.0.90.54670     64128      0 49232      0 ESTABLISHED

Getting closer... let's also remove those idle and bound lines:

bash-3.00$ netstat -a -n -f inet -P tcp | \
awk '$2 !~ /^127\.0\./ && $2 !~ /^192\.168\.1\./ && $7 !~ /LISTEN/ && $7 !~ /BOUND/ && $7 !~ /IDLE/'

TCP: IPv4
   Local Address        Remote Address    Swind Send-Q Rwind Recv-Q    State
-------------------- -------------------- ----- ------ ----- ------ -----------
192.168.1.29.22      10.88.0.90.54670     64128      0 49232      0 ESTABLISHED

Yay. Now I can see my SSH login, and more to the point, see that there are no other connections to this host from outside our LAN, which is what I wanted to check.

Show where Windows home directories are

In our AD, user's home directories are stored on various file servers. So when it's time to migrate them to a new file server, how do we determine who needs to get moved off the old one? ldapsearch to the rescue:


ldapsearch -x -LLL -E pr=2000/noprompt -h rov-dc -D Administrator@example.com -W -b 'cn=Users,dc=example,dc=com' -s sub homeDirectory | awk '$1 = /homeDirectory:/ {print $2}' | sort