unwrapping ldapsearch's ldif output
I'm working on a project to access data from my corporate Active Directory server using ldapsearch. The version of ldapsearch that comes with Red Hat Enterprise Server spews out LDIF in column truncated format. That is to say it inserts a carriage return at column 80 of the output.This sed goodie unwraps the ldif output.
UNWRAP=' /^ / {; H; d; }; /^ /! {; x; s/\n //; }; '
Remove numbers from history
Use the following command to give a history listing without the numbers for easier copy and pasting:history | sed 's/^[ 0-9]* //'
Deleting difficult filenames
To delete a file who's file name is a pain to define (eg. ^H^H^H) find it's inode number with the command "ls -il". Use the line below to find and delete the file.find . -inum 12345 | xargs rm
Rename many files using find and perl
Rename a lot of files at once:find . | perl -ne'chomp; next unless -e; $oldname = $_; s/aaa/bbb/; next if -e; rename $oldname, $_'
Change 'aaa' and 'bbb' to what you want to find and replace in the filename
kill process in one line
kill -9 `ps -fea | grep java | grep -v grep | awk '{print $2}'`Open port
iptables -A INPUT -p tcp -i eth0 --dport X -j ACCEPTAdd header/footer to command output
If you want to surround the output of a command by a header or a footer try the following:$ command | cat headerFile - footerFile
For example
$ ls *txt | cat header - footer Here is a list of files: 1.txt 2.txt End of file list
Suspend ssh session
Suppose you have just sshed into a computer and you want to get back to the terminal prompt of the computer you started with. Escape, by default with ssh is "~", so enter "~" followed by "ctl-z" to suspend. You can then use 'fg' to go back to the ssh session.Convert tabs to spaces
Use 'expand' to convert tabs to spaces:$ expand MyFile.txt > notabs
fsck my life
To do a filesystem check on all of your partitions, here's a quick one-liner. It parses out /etc/fstab for the partitions and runs a fsck on them.for dev in `grep dev /etc/fstab | grep -v \#`; do fsck ${dev}; doneActively Monitor a File
This is a way to monitor "/var/log/messages" or any file for certain changes.The example below actively monitors "stuff" for the word "now" and as soon as "now" is added to the file, the contents of msg are sent by email
$ tail -f stuff | awk ' /now/ { system("mail -s \"Now Occured\" mail@foo.com < msg") }'Record your session
Record eveything printed on your terminal screen with the following command:$ script -a
Now start doing stuff and everything is appended to
Edit previous commands with fc
Use the 'fc' command to open your previous command for editing in your default editor. Saving the changes will then run the edited command.'fc -l' will show a list of previous commands to edit and 'fc
List user accounts on a system
cut -d: -f1 /etc/passwd | sort OR getent passwd|cut -d: -f1|sort
Create a Terminal Calculator
Put the following in your .bashrc filefunction calc { echo "${1}"|bc -l; }
Usage:
$ calc 2+2 4 $ calc "sqrt(2)" 1.41421356237309504880
Calendar with today colored [handle single digit dates]
If your version of grep supports coloring matches, you can use the following to give a calendar with the current date colored:cal | grep --color=auto -E \(\ \|^\)$(date +%e)\(\ \|\$\)\|\$
Howto get DVDs playing on Ubuntu Gutsy
Get DVDs playing on Ubuntu Gutsy by installing libdvdcss2.
echo "deb http://packages.medibuntu.org/ gutsy free non-free" | sudo tee -a /etc/apt/sources.list echo "deb-src http://packages.medibuntu.org/ gutsy free non-free" | sudo tee -a /etc/apt/sources.list wget -q http://packages.medibuntu.org/medibuntu-key.gpg -O - | sudo apt-key add - && sudo apt-get update sudo apt-get install libdvdcss2
Remove comments and blank lines
sed '/ *#/d; /^ *$/d' file
Remove comments and blank lines from file
Calendar with current date
Add the following sed commands to cal to get a calendar with the current date marked:cal | sed "s/^/ /;s/$/ /;s/ $(date +%e) / $(date +%e | sed 's/./#/g') /"
Directory Tree
The following alias will print the directory structure from the current directory in tree format.alias dirf='find . -type d | sed -e "s/[^-][^\/]*\// |/g" -e "s/|\([^ ]\)/|-\1/"'
Pipe files to an archive
If you want to select specifically the files to add to an archive you can pipe the output from find (or any command that gives a list of files) to cpio:$ find ./dir/ | cpio -o --format=tar > archive.tar or $ find ./dir/ | cpio -o --format=tar -F test.tar
Run commands on logout
If a file named $HOME/.logout (a file named .logout in your home directory) exists, and the following trap statement is in your .profile, .logout is executed when you logout.Add this to .profile:
trap "$HOME/.logout" 0
Get your IP address
lynx -dump http://whatismyip.com | awk '/^Your/ {print $5}'Convert permissions to octal
Converts the symbolic permissions to octal (ie: numbers) when using 'ls -l':$ls -l | sed -e 's/--x/1/g' -e 's/-w-/2/g' -e 's/-wx/3/g' -e 's/r--/4/g' \ -e 's/r-x/5/g' -e 's/rw-/6/g' -e 's/rwx/7/g' -e 's/---/0/g' -755 1 jrl jrl 111943 2003-10-21 19:57 logscan -644 1 jrl jrl 35468 2003-11-23 16:13 htfoo -700 1 jrl jrl 3100672 2004-05-15 17:00 mutt -644 1 jrl jrl 10162 2005-02-22 14:14 joinstep2.php -777 1 jrl jrl 41079 2005-04-21 13:02 setistats d755 2 jrl jrl 47 2007-10-26 14:41 rf -700 1 jrl jrl 104 2008-02-05 11:26 getcIf you're going to use this, you may want to make an alias rather than type it in each time!
Find matching programs
Sometimes you want to find a program without knowing the full name. This can be done with the following one liner:IFS=: ; for D in $PATH; do for F in $D/*PATTERN*; do [ -x $F ] && echo $F; done; done
For example:
$ IFS=: ; for D in $PATH; do for F in $D/*text*; do [ -x $F ] && echo $F; done; done /usr/bin/gettext /usr/bin/glib-gettextize /usr/bin/gnome-text-editor /usr/bin/xgettext