Commands using echo (1,545)

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Re-read partition table on specified device without rebooting system (here /dev/sda).

Email yourself a short note
I created this so I could send myself an email alert when a long-running job was finished, e.g., $ my_long_job.exe ; quickemail my_long_job.exe has finished

HOME USE ONLY: Get rid of annoying Polkit password prompts
Although the need to type a password to make certain changes to the system may make perfect sense in a business or educational environment, it makes absolutely zero sense to the home user. So, if you’re at home and would rather get work done than be annoyed by what is essentially Linux’s UAC, then this command is for you.

Find out how old a web page is
I used to use the Firefox "View page info" feature a lot to determine how stale the web page I was looking at was. Now that I use mostly Chrome I miss that feature, so here is a command line alternative using wget. The -S says to display the server response, the --spider says to not download any files/pages, just fetch the header. The output goes to stderr, so to grep it you use 2>&1 to combine the stderr stream with stdout, the pipe that to grep for Last-Modified. You can use curl instead if you have it installed, like this: $ curl --head -s http://osswin.sourceforge.net | grep Mod

Recursively search for large files. Show size and location.

Most Commonly Used Grep Options
This is very helpful to place in a shell startup file and will make grep use those options all the time. This example is nice as it won't show those warning messages, skips devices like fifos and pipes, and ignores case by default.

Open screen on the previous command
I often find myself wanting to open screen on whatever command I'm currently running. Unfortunately, opening a fresh screen session spawns a new bash session, which doesn't keep my history, so calling screen directly with the previous command is the only way to go.

Search some text from all files inside a directory

diff the outputs of two programs
I've been looking for this for a long time. Does anybody know how to do this in dash (POSIX shell)? An alternative version might be: $ exiftool img_1.jpg | diff -

Determine the version of a specific package with RPM
In this case, I'm getting the package version for 'redhat-release', but of course, this can be applied to any package installed on the filesystem. This is very handy in scripts that need to determine just the version of the package, without the package name and all the sed and grep hackery to get to the data you want. To find out all the support format strings that 'rpm --qf' supports: $ rpm --querytags


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