Commands tagged function (131)

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List your interfaces and MAC addresses
Requires sysfs mounted on /sys - may only be useful for Linux systems. Could also use "printf '%-8s %s\n' $(basename $f) $(cat $f/address)" instead of echo.

Cap apt-get download speed
apt-get is pretty aggressive when it downloads, potentially hogging the bandwidth of your network. The 25 is in KB, change this to your needs.

convert a line to a space

Print line immediately before a matching regex.
Use this if you don't have access to GNU grep's -B option.

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" }

backup system over ssh, exlucde common dirs

diff the same file in two directories.
This is useful when you're diffing two files of the same name in radically different directory trees. For example: Set $ path1='/some/long/convoluted/path/to/all/of/your/source/from/a/long/dead/machine' then $ path2='/local/version/of/same/file' then run the command. Much easier on the eyes when you're looking back across your command history, especially if you're doing the same diff over and over again.

Search for a line of text in a directory of files recursively (while limiting to certain file extensions)

Strace all signals processes based on a name ( The processes already started... ) with bash built-in
Especially for sysadmins when they don't want to waste time to add -p flag on the N processes of a processname. In the old school, you did ; $ pgrep processname and typing strace -f -p 456 -p 678 -p 974... You can add -f argument to the function. That way, the function will deal with pgrep to match the command-line. Example : $ processname -f jrockit

Get curenttly playing track in Last.fm radio


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