Commands using echo (1,545)

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a simple bash one-liner to create php file and call php function

Poke a Webserver to see what it's powered by.
the good: Server: Apache/2.2.8 (Ubuntu) PHP/5.2.4-2ubuntu5.4 with Suhosin-Patch the bad: Server: Microsoft-IIS/6.0 and the ugly: Server: Apache/2.2.10 (Win32) mod_ssl/2.2.10 OpenSSL/0.9.8i PHP/5.2.6

Adding Prefix to File name
Good old bracket expansion :-) For large numbers of files, "rename" will spare you the for-loop, or the find/exec...

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 http headers for an url

Shows space used by each directory of the root filesystem excluding mountpoints/external filesystems (and sort the output)
Useful to see at glance which directory under the root file is using most space

history manipulation
make make install !-2 && !-1

Display a markdown file in a new tab in firefox

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

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 }


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