This command displays a list of lines that are longer than 72 characters. I use this command to identify those lines in my scripts and cut them short the way I like it.

Removes trailing newline; colon becomes record separator and newline becomes field separator, only the first field is ever printed. Replaces empty entries with $PWD. Also prepend relative directories (like ".") with the current directory ($PWD). Can change PWD with env(1) to get tricky in (non-Bourne) scripts.

This is really fast :)

204753

real 0m0.191s

user 0m0.068s

sys 0m0.116s

Checks the Gmail ATOM feed for your account, parses it and outputs a list of unread messages.

For some reason sed gets stuck on OS X, so here's a Perl version for the Mac:

If you want to see the name of the last person, who added a message to the conversation, change the greediness of the operators like this:

Does not require input to function or complete. Number of iterations controlled by shell variable $NUM.

Have wc work on each file then add up the total with awk; get a 43% speed increase on RHEL over using "-exec cat|wc -l" and a 67% increase on my Ubuntu laptop (this is with 10MB of data in 767 files).

needs no GNU tools, as far as I see it

saves one command. Needs GNU grep though :-(

The grep switches eliminate the need for awk and sed. Modifying vim with -p will show all files in separate tabs, -o in separate vim windows. Just wish it didn't hose my terminal once I exit vim!!

This will drop you into vim to edit all files that contain your grep string.

Check which files are opened by Firefox then sort by largest size (in MB). You can see all files opened by just replacing grep to "/". Useful if you'd like to debug and check which extensions or files are taking too much memory resources in Firefox.

( IFS=:; for i in $PATH; do echo $i; done; )

echo $PATH|sed -e 's/:/\n/g' # but the tr one is even better of course

echo $PATH|xargs -d: -i echo {} # but this comes up with an extra blank line; can't figure out why and don't have the time :(

echo $PATH|cut -d: --output-delimiter='

' -f1-99 # note -- you have to hit ENTER after the first QUOTE, then type the second one. Sneaky, huh?

echo $PATH | perl -l -0x3a -pe 1 # same darn extra new line; again no time to investigate

echo $PATH|perl -pe 's/:/\n/g' # too obvious; clearly I'm running out of ideas :-)

More of the same but with more elaborate perl-fu :-)

?Cat and grep? You can use only grep ("grep \. filename"). Better option is awk.

Breaks down and numbers each line and it's fields. This is really useful when you are going to parse something with awk but aren't sure exactly where to start.

converts any number on the 'stdin' to SI notation. My version limits to 3 digits of precious (working with 10% resistors).

the f is for file and - stdout, This way little shorter.

I Like copy-directory function It does the job but looks like SH**, and this doesn't understand folders with whitespaces and can only handle full path, but otherwise fine,

function copy-directory () { ; FrDir="$(echo $1 | sed 's:/: :g' | awk '/ / {print $NF}')" ; SiZe="$(du -sb $1 | awk '{print $1}')" ; (cd $1 ; cd .. ; tar c $FrDir/ )|pv -s $SiZe|(cd $2 ; tar x ) ; }

grep -o puts each occurrence in a separate line

grep's -c outputs how may matches there are for a given file as "file:N", cut takes the N's and awk does the sum.

awk can clear the screen while displaying output. This is a handy way of seeing how many lines a tail -f has hit or see how many files find has found. On solaris, you may have to use 'nawk' and your machine needs 'tput'

Basically it creates a typical word list file from any normal text.

Helpful when we want to do mass file renaming(especially mp3s).

You need sysstat and gawk for this to work.