advanced-bash-techniques

14y, 297d ago [edited]

advanced bash techniques

find and change all files

sudo find . -type f -print0 | xargs -0 ls -hal

sudo find . -type f -print0 | xargs -0 sudo chown www-data:www-data

sudo find . -type f -print0 | xargs -0 sudo chmod 0644

find and change all directories:

sudo find . -type d -print0 | xargs -0 sudo chmod 0775

Remove a particular line from all files in a directory

for file in /tmp/test/*
  do
    cp -p $file $file.tmp
    egrep -v "RegexToRemove" $file.tmp > $file
    rm -rf $file.tmp
  done

apache logs count unique ip addresses

sudo cat access.log | awk '{ print $1; }' | sort | uniq -c | sort -n

Bash Perl search and replace multiple files one liner

perl -pi -w -e 's/search/replace/g;' *.extension

explanation:

-e

means execute the following line of code.

-i

means edit in-place

-w

write warnings

-p

loop

Bash sed search and replace multiple files one liner

sed -i'' -e 's/search/replace/g' *

Get a coma separated list of libvirt guests

virsh list | egrep -v 'Domain|Name|----|^$' | awk '{printf "%s," , $2}' > /tmp/virthosts

advanced bash techniques
============================

find and change all files

.. code-block:: bash

sudo find . -type f -print0 | xargs -0 ls -hal

sudo find . -type f -print0 | xargs -0 sudo chown www-data:www-data

sudo find . -type f -print0 | xargs -0 sudo chmod 0644

find and change all directories:

sudo find . -type d -print0 | xargs -0 sudo chmod 0775

Remove a particular line from all files in a directory
============================================================

.. code-block:: bash

for file in /tmp/test/*
   do
     cp -p $file $file.tmp
     egrep -v "RegexToRemove" $file.tmp > $file
     rm -rf $file.tmp
   done

apache logs count unique ip addresses
=========================================

.. code-block:: bash

sudo cat access.log | awk '{ print $1; }' | sort | uniq -c | sort -n

Bash Perl search and replace multiple files one liner
=======================================================

.. code-block:: perl

perl -pi -w -e 's/search/replace/g;' *.extension

explanation:

**-e** 
  means execute the following line of code.

**-i**
  means edit in-place

**-w**
  write warnings

**-p**
  loop

Bash sed search and replace multiple files one liner
============================================================

.. code-block:: sed

sed -i'' -e 's/search/replace/g' *

Get a coma separated list of libvirt guests
==================================================

.. code-block:: bash

virsh list | egrep -v 'Domain|Name|----|^$' | awk '{printf "%s," , $2}' > /tmp/virthosts

Comments

Leave first comment to start a conversation!