Monday, June 18, 2018

nice collection of bash tips

Nicely done! Article by Steve Ovens: "Bash tips for everyday at the command line"

Ovens posted the following at the end, for the "tl;dr" crowd:

Appendix 1. List of tips and tricks covered

# History related
ctrl + r (reverse search)
!! (rerun last command)
!* (reuse arguments from previous command)
!$ (use last argument of last command)
shopt -s histappend (allow multiple terminals to write to the history file)
history | awk 'BEGIN {FS="[ \t]+|\\|"} {print $3}' | sort | uniq -c | sort -nr | head (list the most used history commands)

# File and navigation
cp /home/foo/realllylongname.cpp{,-old}
cd -
rename 's/text_to_find/been_renamed/' *.txt
export CDPATH='/var/log:~' (variable is used with the cd built-in.)

# Colourize bash

# enable colors
eval "`dircolors -b`"
# force ls to always use color and type indicators
alias ls='ls -hF --color=auto'
# make the dir command work kinda like in windows (long format)
alias dir='ls --color=auto --format=long'
# make grep highlight results using color
export GREP_OPTIONS='--color=auto'

export LESS_TERMCAP_mb=$'\E[01;31m'
export LESS_TERMCAP_md=$'\E[01;33m'
export LESS_TERMCAP_me=$'\E[0m'
export LESS_TERMCAP_se=$'\E[0m' # end the info box
export LESS_TERMCAP_so=$'\E[01;42;30m' # begin the info box
export LESS_TERMCAP_ue=$'\E[0m'
export LESS_TERMCAP_us=$'\E[01;36m'

# Bash shortcuts
    shopt -s cdspell (corrects typoos)
    ctrl + _ (undo)
    ctrl + arrow (move forward a word)
    ctrl + a (move cursor to start)
    ctrl + e (move cursor to end)
    ctrl + k (cuts everything after the cursor)
    ctrl + l (clears screen)
    ctrl + q (resume command that is in the foreground)
    ctrl + s (pause a long running command in the foreground)
    ctrl + t (swap two characters)
    ctrl + u (cuts everything before the cursor)
    ctrl + x + ctrl + e (opens the command string in an editor so that you can edit it before it runs)
    ctrl + x + * (expand glob/star)
    ctrl + xx (move to the opposite end of the line)
    ctrl + y (pastes from the buffer)
    ctrl + shift + c/v (copy/paste into terminal)

# Running commands in sequence
&& (run second command if the first is successful)
; (run second command regardless of success of first one)

# Redirecting I/O
2>&1 (redirect stdout and stderr to a file)

# check for open ports
echo > /dev/tcp//
`` (use back ticks to shell out)

# Examine executable
which
file
command -V (tells you whether is a built-in, binary or alias)

Thursday, June 7, 2018

overwhelmed by plastic

June 5 is marked by the United Nations as World Environment Day, a day set aside since 1974 to promote “worldwide awareness and action for the protection of our environment.” This year’s theme is “beat plastic pollution.”
-- from: World Environment Day 2018: ‘Beat Plastic Pollution’
   The Atlantic, June 5, 2018

Stunning photos. What are we doing to our world??