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$ cat mod_log_config.c | shmore or $ shmore < mod_log_config.c Most pagers like less, more, most, and others require additional processes to be loaded, additional cpu time used, and if that wasn't bad enough, most of them modify the output in ways that can be undesirable. What I wanted was a "more" pager that was basically the same as running: $ cat file Without modifying the output and without additional processes being created, cpu used, etc. Normally if you want to scroll the output of cat file without modifying the output I would have to scroll back my terminal or screen buffer because less modifies the output. After looking over many examples ranging from builtin cat functions created for csh, zsh, ksh, sh, and bash from the 80's, 90s, and more recent examples shipped with bash 4, and after much trial and error, I finally came up with something that satisifed my objective. It automatically adjusts to the size of your terminal window by using the LINES variable (or 80 lines if that is empty) so This is a great function that will work as long as your shell works, so it will work just find if you are booted in single user mode and your /usr/bin directory is missing (where less and other pagers can be). Using builtins like this is fantastic and is comparable to how busybox works, as long as your shell works this will work. One caveat/note: I always have access to a color terminal, and I always setup both the termcap and the terminfo packages for color terminals (and/or ncurses and slang), so for that reason I stuck the $ tput setab 4; tput setaf 7 command at the beginning of the function, so it only runs 1 time, and that causes the -- SHMore -- prompt to have a blue background and bright white text. This is one of hundreds of functions I have in my .bash_profile at AskApache.com, but actually won't be included till the next update. If you can improve this in any way at all please let me know, I would be very grateful! ( Like one thing I want is to be able to continue to the next screen by pressing any key instead of now having to press enter to continue)

extract email addresses from some file (or any other pattern)

Find usb device in realtime
Using this command you can track a moment when usb device was attached.

Convert seconds to [DD:][HH:]MM:SS
Converts any number of seconds into days, hours, minutes and seconds. sec2dhms() { declare -i SS="$1" D=$(( SS / 86400 )) H=$(( SS % 86400 / 3600 )) M=$(( SS % 3600 / 60 )) S=$(( SS % 60 )) [ "$D" -gt 0 ] && echo -n "${D}:" [ "$H" -gt 0 ] && printf "%02g:" "$H" printf "%02g:%02g\n" "$M" "$S" }

Readd all files is missing from svn repo
When working on a big proeject with SVN, you create quite much files, for now! Can just sit here and type svn add for all of them! svn status will return a list of all of file which get ?(not add), "M"(Modified), "D"(Deleted)! This code just grep "?" flag, then add it into SVN again!

Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

Turn white color to transparent for a series of png images
mogrify can be used like convert. The difference is that mogrify overwrites files: http://www.imagemagick.org/www/mogrify.html Of course, other source colors can be used as well.

list block devices
Shows all block devices in a tree with descruptions of what they are.

Burn an audio CD.
My variation on an audio burning command from commandlinefu - this one doesn't crap out if you want to burn a CD in a directory whose permissions don't allow it, and instead rips everything to /tmp. If you mount your music partition like I do using Samba, you probably don't have write permission inside that file system in order to create the temporary directory other audio burning commands here use. Not a bad idea to add cdrom to your groups, and /bin/eject with visudo.

shell function to make gnu info act like man.
For those who hate navigating info pages, a shell function which will dump the contents to stdout, then page it through less, thus acting like 'man'.


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