The first grep any line with pod-feed in it plus the following five lines. The second grep throws out any line not containing . sed removes the leading four spaces then and the trailing . Using a colon as sed's separating character avoids having to escape the /. Works ok with Mythbuntu 9.04 (used mostly as a three line bash script). Show Sample Output
The above is an example of grabbing only the first column. You can define the start and end points specifically by chacater position using the following command:
while read l; do echo ${l:10:40}; done < three-column-list.txt > column-c10-c40.txt
Of course, it doesn't have to be a column, or extraction, it can be replacement
while read l; do echo ${l/foo/bar}; done < list-with-foo.txt > list-with-bar.txt
Read more about parameter expansion here:
http://wiki.bash-hackers.org/syntax/pe
Think of this as an alternative to awk or sed for file operations
It works best as part of a function, such as the following: MUSICROOT=~/Music function fplay { if [ $1 = '-v' ]; then shift 1 find -E $MUSICROOT -type f -iname "*$**" -iregex '.*\.(3g[2|p]|aac|ac3|adts|aif[c|f]?|amr|and|au|caf|m4[a|r|v]|mp[1-4|a]|mpeg[0,9]?|sd2|wav)' -print -exec afplay "{}" \; & else find -E $MUSICROOT -type f -iname "*$**" -iregex '.*\.(3g[2|p]|aac|ac3|adts|aif[c|f]?|amr|and|au|caf|m4[a|r|v]|mp[1-4|a]|mpeg[0,9]?|sd2|wav)' -exec afplay "{}" \; & fi }
This version uses netcat to check a particular service.
Work out last months value Show Sample Output
This function defines a command line calculator that handles everything pythons math module can handle, e.g. trigonometric functions, sqrt, log, erf, ... (see http://docs.python.org/library/math.html). It even knows about the constants pi and e. Show Sample Output
Grabs the cmdline used to execute the process, and the environment that the process is being run under. This is much different than the 'env' command, which only lists the environment for the shell. This is very useful (to me at least) to debug various processes on my server. For example, this lets me see the environment that my apache, mysqld, bind, and other server processes have.
Here's a function I use:
aa_ps_all () { ( cd /proc && command ps -A -opid= | xargs -I'{}' sh -c 'test $PPID -ne {}&&test -r {}/cmdline&&echo -e "\n[{}]"&&tr -s "\000" " "<{}/cmdline&&echo&&tr -s "\000\033" "\nE"<{}/environ|sort&&cat {}/limits' ); }
From my .bash_profile at http://www.askapache.com/linux-unix/bash_profile-functions-advanced-shell.html
Show Sample Output
Only to logout all users except root
I've had a horrible time trying to pipe the output of some shell built-ins like 'time' to other programs. The built-in doesn't output to stdout or stderr most of the time but using the above will let you pipe the output to something else. Show Sample Output
Adds the time in 12hr AM/PM format to the beginning of a prompt. Change \@ to \t for 24-hour time or \T for 12hr without AM/PM. To keep the time the next time you open a terminal, edit ~/.bashrc and stick the command at the bottom. Show Sample Output
This command will copy command's output into your local clipboard
Python Alternative Show Sample Output
Makes bash-4.x like zsh. Automatic cd into a directory if a command with that name doesnt exists. Ready for your ~/.bashrc file Show Sample Output
Nobody wants the boss to notice when you're slacking off. This will fill your shell with random data, parts of it highlighted. Note that 'highlight' is the Perl module App::highlight, not "a universal sourcecode to formatted text converter." You'll also need Term::ANSIColor. Show Sample Output
No need for further filedes or substitution for splitting. Simply use read a b
Inverse grep, to find files without the string
This is a simple bash function and a key binding that uses commandlinefu's simple and easy search API. It prompts for a search term, then it uses curl to search commandline fu, and highlights the search results with less.
If you use new features of a certain Bash version in your shell script, make sure that it actually runs with the required version.
easier way to recursively change files to lowercase using rename instead
If you're only using -m or -k, you will need to remember they are either in Megabyte or kilobyte forms. So by using -B, it gives you the unit of the size measurement, which helps you from reading the result faster. You can try with -B K as well. Show Sample Output
This way, you can specify how many hours in which you want your machine to shut down. Show Sample Output
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