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List files with full path
Prints contents of current directory with the full path prepended to each entry. You can add '-type f' if you don't want the directories to show up (for those less familiar with find). I can't believe ls doesn't have an option for this.

Print every Nth line
Sometimes commands give you too much feedback. Perhaps 1/100th might be enough. If so, every() is for you. $ my_verbose_command | every 100 will print every 100th line of output. Specifically, it will print lines 100, 200, 300, etc If you use a negative argument it will print the *first* of a block, $ my_verbose_command | every -100 It will print lines 1, 101, 201, 301, etc The function wraps up this useful sed snippet: $ ... | sed -n '0~100p' don't print anything by default $ sed -n starting at line 0, then every hundred lines ( ~100 ) print. $ '0~100p' There's also some bash magic to test if the number is negative: we want character 0, length 1, of variable N. $ ${N:0:1} If it *is* negative, strip off the first character ${N:1} is character 1 onwards (second actual character).

pretend to be busy in office to enjoy a cup of coffee
The first parameter after timeout is the key parameter; number of seconds to wait. With a 6 you have 600 seconds for your coffee break (10min).

lists files and folders in a folder
lists files and folders in a folder with summary.

Truncate long strings in columns and use custom header names
Using the --table-truncate ( -T ) option, you can specify the columns you will allow to be truncated. This helps when you have some columns that are unusually long, or a small terminal window. In this example we will print out the /etc/passwd file in columns. We are using a colon as our separator ( -s: ), defining that we want table output ( -t ), defining the column names ( -N ) and allowing the column NAME to be truncated ( -T ).

Find directories under home directory with 777 permissions, change to 755, and list them on console

Browse system RAM in a human readable form
This command lets you see and scroll through all of the strings that are stored in the RAM at any given time. Press space bar to scroll through to see more pages (or use the arrow keys etc). Sometimes if you don't save that file that you were working on or want to get back something you closed it can be found floating around in here! The awk command only shows lines that are longer than 20 characters (to avoid seeing lots of junk that probably isn't "human readable"). If you want to dump the whole thing to a file replace the final '| less' with '> memorydump'. This is great for searching through many times (and with the added bonus that it doesn't overwrite any memory...). Here's a neat example to show up conversations that were had in pidgin (will probably work after it has been closed)... $sudo cat /proc/kcore | strings | grep '([0-9]\{2\}:[0-9]\{2\}:[0-9]\{2\})' (depending on sudo settings it might be best to run $sudo su first to get to a # prompt)

dd with progress bar and statistics
This command utilizes 'pv' to show dd's progress. Notes on use with dd: -- dd block size (bs=...) is a widely debated command-line switch and should usually be between 1024 and 4096. You won't see much performance improvements beyond 4096, but regardless of the block size, dd will transfer every bit of data. -- pv's switch, '-s' should be as close to the size of the data source as possible. -- dd's out file, 'of=...' can be anything as the data within that file are the same regardless of the filename / extension.

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" }

Line Separator That is Width of Terminal
Creates a line seperator that will be the width of your window.


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