More linux snippets · flogiston

Need to remove all those ^M characters from a DOS file? Try

tr -d \\r < dosfile > newfile

Need to find which process is taking up a certain port?

sudo fuser -n tcp 8080

get details on a certain process?

ps -eaf | grep 22450

Show which processes are using which sockets

sudo netstat -nlp

Split a file on x lines

split -l 409000 catalina.out

this will generate files like xaa, xab, xac, xad, ....
Join these split files back

cat x* > joined.log

Analyse a logfile and retrieve only the ERROR lines and their Cause:

egrep 'Cause|ERROR' catalina.out > catalina_errors.out

or using grep (don't forget to escape the pipe):

grep "Cause\|ERROR" catalina.out

Shopt:

shopt -s nocaseglob

Use wget to follow hyperlinks from a text file, log the server response and exclude media files

wget -b -H -r --level=1 --no-parent -e robots=off -o wget.log -O output.log  -i input.txt --server-response --save-headers -R *.gif,*.css,*.xml,*.swf,*.png,*.jpg,*.xml,*.js,\' --follow-tags=a

or simply

wget -b -o wget.log -O output.log  -i input.txt --server-response

Then grep the logfile to detect all links and if they failed:

cat wget.log | grep '\-\-\|HTTP\|failed'

Open winmail.dat files on Ubuntu:

sudo apt-get install tnef

tnef winmail.dat

Fix corrupted zip files in Linux

zip –F "filename.zip"

And if that doesn't work: make zip work harder:

zip –FF "filename.zip"

And finally a simple regex to match 4 or more consecutive letters or numbers

([a-z-0-9])\1{3,}

To end on a lighter note: a nice website containing funny source code comments:
http://cobaia.net/2010/09/top-funny-source-code-comments/