Commands by unixmonkey3142 (3)

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Display summary of git commit ids and messages for a given branch
Useful when quickly looking for a commit id from a branch to use with git cherry-pick.

Floating point power p of x
One pipe less.

Mount a partition from dd disk image
Assuming we have a disk image, ie. created by $dd if=/dev/sda of=image.dd we can check the image's partition layout with $fdisk -ul image.dd then, we substitute "x" with starting sector of the partition we want to mount. This example assumes that the disk uses 512 B sectors

create an emergency swapfile when the existing swap space is getting tight
Create a temporary file that acts as swap space. In this example it's a 1GB file at the root of the file system. This additional capacity is added to the existing swap space.

Ask for a password, the passwd-style
You can ask repeatedly for a non-blank password using this function: function read_password() { while [ ! -n "$USER_PASSWORD" ]; do read -s -p"Password: " USER_PASSWORD if [ ! -n "$USER_PASSWORD" ]; then echo "ERROR: You must specify a valid password, please try again" fi echo done } Also you can set a time out (in seconds) to write the password read -t 10 -s -p"Password: " USER_PASSWORD_VARIABLE if [ ! $? -eq 0 ]; then echo "Time out!" fi

show ALL iptable rules
show your current iptable rules from every available iptable table

Convert CSV to JSON
Replace 'csv_file.csv' with your filename.

Find the package that installed a command

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 Entire YouTube Channel - all of a user's videos
create the function then run 'yt-chanrip username' to download that user's entire channel. uses youtube-dl and the GData API. similar to http://www.commandlinefu.com/commands/view/3154/download-youtube-playlist


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