Commands by jcchurch (1)

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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" }

Download all images from a 4chan thread
Useful for ripping wallpaper from 4chan.org/wg

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"

Get IP from hostname

Replace spaces in filenames with underscores
I realize there's a few of these out there, but none exactly in this form, which seems the cleanest to me

pdfcount: get number of pages in a PDF file

Do some learning...
I like it sorted... 2> /dev/null was also needless, since our pipes already select stdin, only.

Monitor iptables in realtime

identify NEEDED sonames in a path
This works in combination with http://www.commandlinefu.com/commands/view/10496/identify-exported-sonames-in-a-path as it reports the NEEDED entries present in the files within a given path. You can then compare it with the libraries that are exported to make sure that, when cross-building a firmware image, you're not bringing in dependencies from the build host. The short version of it as can be seen in the same output is $ scanelf -RBnq -F "+n#f" $1 | tr ',' '\n' | sort -u

Lists the size of certain file in every 10 seconds
watch is a command especially designed for doing this job


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