SHELL

# export on source
set -a; source .env; set +a

visudo
myron ALL=(ALL) NOPASSWD:ALL

. <(flux completion bash) # completions

# debugging
set -xv 

cmd | tee $(date '+%Y-%m-%d-%H%M%S-name.log')

# iTerm search. find 500s in log
HTTP[^\s]+\s5\d\d\s

# auto expanding
echo {a,b}.name
ap -i ./inv-lab.yml ./playbook-upgrade.yml \
-l $(echo {k7,ph}.overton-design.com|tr ' ' ',')

# exit on error
#! /bin/bash -eu
set -o pipefail

# dump env and functions
typeset

# see definition
type myfunc

# tail from the beginning
tail -0F

# xargs
echo webserver loadbalancer database | tr ' ' '\n' \
| xargs -I % -P 3 bash -c 'ansible-playbook $1.yml' -- %


# remove root from list of files
for f in /sys/devices/system/cpu/vulnerabilities/*; \
do echo "${f##*/} -" $(cat "$f"); done

BASH

^u - kill left of cursor

^k - kill right

^w - kill word to left

ZSH

https://github.com/ohmyzsh/ohmyzsh

https://github.com/woefe/git-prompt.zsh

https://github.com/zplug/zplug

https://git-scm.com/book/en/v2/Appendix-A%3A-Git-in-Other-Environments-Git-in-Zsh

Capturing output

Links
- Shell Tricks

Shell Countdown

countdown() {
    declare desc="A simple countdown. Source: https://superuser.com/a/611582"
    local seconds="${1}"
    local d=$(($(date +%s) + "${seconds}"))
    while [ "$d" -ge `date +%s` ]; do
        echo -ne "$(date -u --date @$(($d - `date +%s`)) +%H:%M:%S)\r";
        sleep 0.1
    done
}

Counting

# steps
for i in $(seq 0 5 20); do
    echo $i  # Outputs: 0 5 10 15 20
done

for i in {0..20..5}; do
    echo $i  # Outputs: 0 5 10 15 20
done

sed sed_i

function sed_i {
   if test "$(uname)" == "Darwin"
   then
      sed -i '' "$@"
      return $?
   else
      sed -i "$@"
      return $?
   fi
}

Sequences

for i in {0..9}; do echo $i; done
for i in `seq 1 5`;do x; done

completions

complete #list
complete -F _asdf b # assign to function

# load from tools like eksctl
. <(eksctl completion bash)

Find base dir

DIR=$(dirname $([ -L $0 ] && readlink $0 || echo $0))
DIR=$(cd $DIR>/dev/null; pwd -P)

find all extensions in a directory
- https://stackoverflow.com/questions/1842254/how-can-i-find-all-of-the-distinct-file-extensions-in-a-folder-hierarchy
```
find . -type f -path '*/.git*' -prune -o -print \
|while read f; \
 do echo ${f##*.}; done \
|sort -u
```

Remove 0x0d line-endings
```
sed_i 's/\r$//g' /entrypoint
```

Wait for file

until [ -f /tmp/examplefile.txt ]
do
     sleep 5
done
echo "File found"
exit

If else
```
if 
```

Local variables

func() {
  local arg1="${1}"
  local x="${2%/}"

If user does not have a shell
```
su - -s /bin/bash tomcat8
```

Arrays

declare -A aliases
aliases=(
	[mainline]='1 1.13 latest'
	[stable]='1.12'
)
versions=( */ )
versions=( "${versions[@]%/}" ) # add to existing

Resolve path

# Need to play with this
self="$(basename "$BASH_SOURCE")"
cd "$(dirname "$(readlink -f "$BASH_SOURCE")")"

Check remote shell vars
```
echo env |ssh -T mdc |grep TARG
```

Test arg processing

#!/bin/sh
echo -------------
for f in "$@"; do
    echo \"$f\"
done


#!/bin/sh
function command () {
    echo
    echo "command line: $@"
    echo "command output:"
    echo "-------------------------------"
    "$@"
    code=$?
    echo "-------------------------------"
    return $code
}

./mro.2 a b c
./mro.2 "a b" c
./mro.2 a "b c"

command ./mro.2 a b c
command ./mro.2 "a b" c
command ./mro.2 a "b c"

Option processing

OPTIND=1
while getopts "hdp" opt; do
    case "$opt" in
        h)   usage ;;
        '?') usage ;;
        d) PROFILE=dev ;;
        p) PROFILE=prod ;;
        :)
            echo "Option -$OPTARG requires an argument." >&2
            exit 1
            ;;
    esac
done
shift "$((OPTIND-1))" # Shift off the options and optional --.

Gen random strings

Random Strings

export CHART_BUCKET=s3://example-chart-store-$(cat /dev/random | LC_ALL=C tr -dc "[:alpha:]" | tr '[:upper:]' '[:lower:]' | head -c 32)

openssl rand 16 -hex
node -e "console.log(require('crypto').randomBytes(256).toString('base64'));"
uuidgen
pwgen 50 1 -s > passphrase
# Or use KeePassX generator

ruby -rsecurerandom -e 'puts SecureRandom.hex(32)'

cat /proc/sys/kernel/random/uuid

BASH rc