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Save a file you edited in vim without the needed permissions (no echo)
Write a file you edited in Vim but that you do not have the permissions to write to (unless you use sudo.) Same as #1204 but without the echo to stdout that I find annoying.

ASCII art of yourself
Use libcaca to render ascii chars on the webcam input... or don't.

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).

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" }

Find usb device
I often use it to find recently added ou removed device, or using find in /dev, or anything similar. Just run the command, plug the device, and wait to see him and only him

Delete backward from cursor, useful when you enter the wrong password

count total number of lines of ruby code
Adapted from http://stackoverflow.com/questions/1358540/how-to-count-all-the-lines-of-code-in-a-directory-recursively#answer-1359246

list files recursively by size

Know which modules are loaded on an Apache server
This let you know which modules has loaded the Apache server, very useful to know if the mod_rewrite is ready to use.

Print a list of standard error codes and descriptions.
Written by jmcnamara Taken from http://www.perlmonks.org/?node_id=274896


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