A Couple of Useful Snippets from My Shell Config

| Comments

I’ve been slowly and incrementally working on cleaning up my shell config. I’ve been procrastinating over my persist and forget system for quite a while now. I have it up and working here just fine, but I built it and its extra git repository in place. I need to automate the installation and configuration process and I would also like to make sure it isn’t likely to eat anyone’s file before I release it.

In the mean-time, though, I have been digging through my configuration and I’ve found a few gems that I would like to list here. I use these under zsh but I am pretty sure they will work fine under bash as well.

Quickly share files on the public Internet with Python and SSH

I see ‘python -m SimpleHTTPServer’ one liner all the time. By itself this one is pretty useless for me. I almost never need to share something with anyone on my local network. I use this function instead:

My webshare function
1
2
3
4
5
6
7
8
9
10
11
12

webshare () {
  local SSHHOST=patshead.com
  local SSHPORT=9999

  python -m SimpleHTTPServer &
  local PID=$!

  echo http://$SSHHOST:$SSHPORT | xclip
  echo Press enter to stop sharing, http://$SSHHOST:$SSHPORT copied to primary selection
  /usr/bin/ssh -R $SSHPORT:127.0.0.1:8000 $SSHHOST 'read'
  kill $PID
}

This does require you to have a server out on the Internet that you can ssh into. For my purposes, this fills a gap somewhere between a pastebin and something like Dropbox. I use it when I have a handful of files I want someone to take a look at.

A smarter tail command

I lifted this one from commandlinefu.com:

My tail function
1
2
3
4
5
6
7
8
9
10
11
12
13
14

tail() {
  local thbin="/usr/bin/tail"
  local fc lpf thbin

  if [ "${1:0:1}" != "-" ]; then
    fc=$(($#==0?1:$#))
    lpf="$((($LINES - 3 - 2 * $fc) / $fc))"
    lpf="$(($lpf<1?2:$lpf))"

    [ $fc -eq 1 ] && $thbin -n $lpf "$@" | /usr/bin/fold -w $COLUMNS | $thbin -n
  else
    $thbin "$@"
  fi
}

I really like this one. This tail wrapper checks the size of the terminal window and makes sure it shows you just a bit less than a screen full of output. It even takes long lines into account.

Automatically managing a “scratch” directory

This function was heavily inspired by an entry on Marcin Kulik’s blog:

`` bash My function to create a new scratch directory function ns { local cur_dir="$HOME/tmp/scratch/current" local new_dir="$HOME/tmp/scratch/date +‘%s’`”

mv $cur_dir $new_dir mkdir $cur_dir cd ~/scratch echo “New scratch dir ready” }

I’m always creating new scratch directories to work in, so I really liked his idea of creating a function to help manage the process.

I didn’t change his implementation too much. The only real difference is that my symlink never changes. I’m just moving the old, real scratch directory out of the way and putting a new one back in its place.

Comments