Commands using grep

Replace * with any filename matching glob or an individual filename

This is useful for displaying a portion of a FILE that contains an error at line NUMBER

Useful to know, especially if you are dealing with output configurations in block size.

Tested on 'Red Hat'.

A good way to understand what you've let yourself in for. Potential project metric could be the count:

automatically add and remove files in subversion so that you don't have to do it through the annoying svn commands anymore

This is a simple but useful command to search for multiple terms in a file at once. This prevents you from having to do mutliple grep's of the same file.

Quick and easy way of validating a date format of yyyy-mm-dd and returning a boolean, the regex can easily be upgraded to handle "in betweens" for mm dd or to validate other types of strings, ex. ip address.

Boolean output could easily be piped into a condition for a more complete one-liner.

bash.org is a collection of funny quotes from IRC.

WARNING: some of the quotes contain "adult" jokes... may be embarrassing if your boss sees them...

Thanks to Chen for the idea and initial version!

This script downloads a page with random quotes, filters the html to retrieve just one liners quotes and outputs the first one.

Just barely under the required 255 chars :)

Improvment:

You can replace the head -1 at the end by:

which will separate the quotes with a "%" and place it in the file.

and then:

which will make the file ready for the fortune command

and then you can:

which will give you a random quote from those in the downloaded file.

I download a file periodically and then use the fortune in .bashrc so I see a funny quote every time I open a terminal.

Find all corrupted jpeg in the current directory, find a file with the same name in a source directory hierarchy and copy it over the corrupted jpeg file.

Convenient to run on a large bunch of jpeg files copied from an unsure medium.

Needs the jpeginfo tool, found in the jpeginfo package (on debian at least).

I have a bash alias for this command line and find it useful for searching C code for error messages.

The -H tells grep to print the filename. you can omit the -i to match the case exactly or keep the -i for case-insensitive matching.

This find command find all .c and .h files

This prints a summary of your referers from your logs as long as they occurred a certain number of times (in this case 500). The grep command excludes the terms, I add this in to remove results Im not interested in.

This is a working version, though probably clumsy, of the script submitted by felix001. This works on ubuntu and CygWin. This would be great as a bash function, defined in .bashrc. Additionally it would work as a script put in the path.

This command might not be useful for most of us, I just wanted to share it to show power of command line.

Download simple text version of novel David Copperfield from Poject Gutenberg and then generate a single column of words after which occurences of each word is counted by sort | uniq -c combination.

This command removes numbers and single characters from count. I'm sure you can write a shorter version.

Ok so it's rellay useless line and I sorry for that, furthermore that's nothing optimized at all...

At the beginning I didn't managed by using netstat -p to print out which process was handling that open port 4444, I realize at the end I was not root and security restrictions applied ;p

It's nevertheless a (good ?) way to see how ps(tree) works, as it acts exactly the same way by reading in /proc

So for a specific port, this line returns the calling command line of every thread that handle the associated socket

This will, for an application that has already been removed but had its configuration left behind, purge that configuration from the system. To test it out first, you can remove the last -y, and it will show you what it will purge without actually doing it. I mean it never hurts to check first, "just in case." ;)

Purge all configuration files of removed packages

Useful for removes a package and its depends, for example to remove the gnome desktop environment, also configuration files will be removed, you should be carefully and sure that you want to do this.

Displays only the VGA adapter/chipset being used for the graphics. In this case, it gave me the "M22" and "Mobility Radeon x300" that I needed to research a graphics issue I was having.

Written for linux, the real example is how to produce ascii text graphs based on a numeric value (anything where uniq -c is useful is a good candidate).

Highlights the search pattern in red.

Basically an improvement on an earlier ethtool command line.