====== Linux Tips, Frequently Used Commands ======

More on [[http://www.zytrax.com/tech/web/regex.htm|regular expressions]] and tools.

===== Permissions and groups =====

Set all permissions for group to read write and sticky:
  chmod g+rws . -R

Set group recursively without touching user:
  chown :groupname . -R

===== Find in files =====

Find text in files ([[http://linux.byexamples.com/archives/59/searching-files-with-locate-find-and-grep/ |source]])
  find -name '*.txt' | xargs grep 'txtpattern'

Finding a word in XML files and returning only a certain attribute with only the text value.
  find | xargs grep "stringval" | cut -d '"' -f 2,9 --output-delimiter='    ' | cut -d '<' -f 1 | cut -d '>' -f 1,2 --output-delimiter=''

Press <ctrl>+v, <tab> to write a real tab into the konsole.


===== SVN on steroids =====

After manually deleting a file from an svn working copy, the file remains marked as missing. Manually svn rm-ing the file is one option, but automatically is also possible. The following command perform the preparations for a simple (but stupid) backup. Retrieve the list from svn status and perform svn rm on all missing files or perform svn add for all new files. Put it in a batch file and $1 may be used as location, $2 as optional parameter.
  svn st --ignore-externals $1 $2 | grep ! | cut -f 2 -d '!' | xargs -t -I{} svn rm {}
  svn st --ignore-externals $1 $2 | grep ? | cut -f 2 -d '?' | xargs -t -I{} svn add {}

===== Are you wgetting this? =====

Use wget to download a directory from ftp site without creating host directories etc. Cutdirs is number of dirs in <pathtofolder>.
  wget -rc -nH --timestamping --server-response  --cut-dirs=1 ftp://<user>:<passwrd>@<host>:<port>/<pathtofolder>/<folder>


Use wget to recursively download a directory from http site.
  wget -k -i http://server.com/path
  find -name "index.html" | xargs -i{} wget -c -F -x -nH -i {}
or
  wget -m http://server.com/path
This also creates directory server.com and subsequent directories.

===== I'm touched =====

The touch command can also set the time to a certain value or copy time from a reference file.
  touch -t "200806021936.05" example.txt

===== Finding files modified in period =====

Create a batch file (for example /usr/bin/findinperiod), inspired by [[http://www.unix.com/unix-dummies-questions-answers/14722-files-between-any-two-given-dates.html|jim mcnamara]]:

  tmpfrom=/tmp/findperiodfrom
  tmpto=/tmp/findperiodto
  touch -t $2 $tmpfrom
  touch -t $3 $tmpto
  find $1 -newer $tmpfrom ! -newer $tmpto
  rm $tmpfrom
  rm $tmpto

Use like this, sort using pipe to the sort command:

  findinperiod . 200803220000 200803232359 | sort

===== All to lowercase (SVN) =====

Rename svn files to lowercase:
  find -name "*.*" | sed 's/\(.*\)/\1\n\L\1/' | xargs -L 2 svn mv 

===== Unrar and remove archives =====

This will find all rar files, extract them and remove all rar and r01, r02 etc. files.

  find -name '*.rar' | sed 's/\(.*\)\/\(.*\)\(..\)/unrar e \1\/\2\3 \1\/ \&\& rm \1\/\2??/' | xargs -I{} -i bash -c '{}'

This involves some risks, so be __careful__!
To test what will happen:

  find -name '*.rar' | sed 's/\(.*\)\/\(.*\)\(..\)/unrar e \1\/\2\3 \1\/ \&\& rm \1\/\2??/' | xargs -I{} -i bash -c 'echo "{}"'

===== List unversioned with filesize =====

  svn st --ignore-externals | grep ? | cut -d '?' -f 2 | xargs -I{} du -sh {}

===== Show filesize of new SVN files =====

  svn st --ignore-externals | grep ? | cut -c 8- | xargs -I{} du -sh {} 
~~DISCUSSION~~

===== Pipe replace/escape spaces =====

Escape spaces (' ' => '\ ')
   | sed 's, ,\\&,g'

===== Remove file extension from string =====

   | sed 's/\(.*\).ps/\1/'

===== Find .nfo files containing 'trance' =====

  find -name '*.nfo' | xargs -I{} -i bash -c 'grep trance "{}" && echo "{}"'
===== Bash autocomplete from history =====

In ''/etc/inputrc'', make sure it contains:
  ...
  # mappings for "page up" and "page down" to step to the beginning/end
  # of the history
  # "\e[5~": beginning-of-history
  # "\e[6~": end-of-history
  
  # alternate mappings for "page up" and "page down" to search the history
  "\e[5~": history-search-backward
  "\e[6~": history-search-forward
  ...

[[http://www.electrictoolbox.com/history-search-auto-completion-bash-shell-ubuntu/|reference]]