Commands by umahp44 (1)

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Convert mp3/wav file to asterisk ulaw for music on hold (moh)

Change Random Wallpaper on Gnome 3
Change Random Wallpaper on Gnome 3

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" }

Fixes Centos 6.2 yum's metalink certificate errors
Fix's centos 6.2 yum's error: could not get metalink https://mirrors.fedoraproject.org/metalink?repo=epel-6&arch=x86_64 error was 14: PYCURL ERROR 77 - "Problem with the SSL CA cert (path? access rights?)" Error: Cannot retrieve metalink for repository: epel-source. Please verify its path and try again

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

Binary digits Matrix effect
Silly Perl variant.

Perform a reverse DNS lookup
Performs a reverse DNS lookup, variants include: $ nslookup 74.125.45.100 or: $ host 74.125.45.100

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"

Print IP of any interface. Useful for scripts.

Save xkcd to a pdf with captions
Saves to a PDF with title and alt text of comic. As asked for on http://bbs.archlinux.org/viewtopic.php?id=91100 Change xkcd.com to dynamic.xkcd.com/comics/random for a random comic.


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