Commands by pdxdoughnut (30)

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Execute a command with a timeout
I like much more the perl solution, but without using perl. It launches a backgroup process that will kill the command if it lasts too much. A bigger function: check_with_timeout() { [ "$DEBUG" ] && set -x COMMAND=$1 TIMEOUT=$2 RET=0 # Launch command in backgroup [ ! "$DEBUG" ] && exec 6>&2 # Link file descriptor #6 with stderr. [ ! "$DEBUG" ] && exec 2> /dev/null # Send stderr to null (avoid the Terminated messages) $COMMAND 2>&1 >/dev/null & COMMAND_PID=$! [ "$DEBUG" ] && echo "Background command pid $COMMAND_PID, parent pid $$" # Timer that will kill the command if timesout sleep $TIMEOUT && ps -p $COMMAND_PID -o pid,ppid |grep $$ | awk '{print $1}' | xargs kill & KILLER_PID=$! [ "$DEBUG" ] && echo "Killer command pid $KILLER_PID, parent pid $$" wait $COMMAND_PID RET=$? # Kill the killer timer [ "$DEBUG" ] && ps -e -o pid,ppid |grep $KILLER_PID | awk '{print $1}' | xargs echo "Killing processes: " ps -e -o pid,ppid |grep -v PID | grep $KILLER_PID | awk '{print $1}' | xargs kill wait sleep 1 [ ! "$DEBUG" ] && exec 2>&6 6>&- # Restore stderr and close file descriptor #6. return $RET }

find xargs mv

shell function which allows you to tag files by creating symbolic links directories in a 'tags' folder.
The tag function takes a tag name as its first argument, then a list of files which take that tag. The directory $HOME/tags/tagname will then hold symbolic links to each of the tagged files. This function was inspired by tmsu (found at https://bitbucket.org/oniony/tmsu/wiki/Home). Example: $ tag dog airedale.txt .shizturc weimeraner.pl This will create $HOME/tags/dog which contains symbolic links to airedale.txt .shizturc and weimeraner.pl

Make directories for and mount all iso files in a folder

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"

List your largest installed packages (on Debian/Ubuntu)
dpigs is in the package debian-goodies (debian/ubuntu)

Find and list users who talk like "lolcats"
Greps IRC logs for phrases and lists users who said them.

Get the version of sshd on a remote system
I used this to confirm an upgrade to an SSH daemon was successful

View all file operator expressions for any file, test, stat
Applies each file operator using the built-in test. $ testt /home/askapache/.sq /home/askapache/.sq -a True - file exists. -d True - file is a directory. -e True - file exists. -r True - file is readable by you. -s True - file exists and is not empty. -w True - the file is writable by you. -x True - the file is executable by you. -O True - the file is effectively owned by you. -G True - the file is effectively owned by your group. -N True - the file has been modified since it was last read. Full Function: testt () { local dp; until [ -z "${1:-}" ]; do dp="$1"; [[ ! -a "$1" ]] && dp="$PWD/$dp"; command ls -w $((${COLUMNS:-80}-20)) -lA --color=tty -d "$dp"; [[ -d "$dp" ]] && find "$dp" -mount -depth -wholename "$dp" -printf '%.5m %10M %#15s %#9u %-9g %#5U %-5G %Am/%Ad/%AY %Cm/%Cd/%CY %Tm/%Td/%TY [%Y] %p\n' -a -quit 2> /dev/null; for f in a b c d e f g h L k p r s S t u w x O G N; do test -$f "$dp" && help test | sed "/-$f F/!d" | sed -e 's#^[\t ]*-\([a-zA-Z]\{1\}\) F[A-Z]*[\t ]* True if#-\1 "'$dp'" #g'; done; shift; done }

find geographical location of an ip address
a shorter version


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