Sudo on OS X

http://blog.rongarret.info/2015/08/psa-beware-of-sudo-on-os-x.html

Bash: init from arg

Initialize from argument:
TEST=$(test -n "$1" && echo $1) || { echo "Usage: $0 <path_to_file>"; exit; }

test -z $1 && echo "Usage: $0 <path_to_file>" && exit
TEST=$1

Divide with floating point

awk 'BEGIN {printf "%.2f \n", (11.226 - 8.342)/11.226*100}'
awk 'BEGIN {print (11.226-8.342)/11.226*100}'

Rounding up works by default:
awk 'BEGIN {printf "%.3f \n", (11.226 - 8.342)/11.226*100}'

Filter STDERR only

$ cat warn.pl
#!/usr/bin/env perl
print STDERR "warnings all over the place\n";
print STDOUT "standard output to file descriptor 1\n";

$ exec 3>&1; ./warn.pl 2>&1 >&3 3>&- | awk '{print $5}' 3>&-; exec 3>&-
standard output to file descriptor 1
place

.bashrc

~/.bashrc

~/.bash_profile

export PS1="\[\033[36m\]\u\[\033[m\]@\h:\[\033[32m\]\w\[\033[m\]\$ "
export PS1="\[\033[36m\]\A \[\033[32m\]\w/ \[\033[33m\]\$ \[\033[m\]"
export PS1="\[\033[32m\]\w/ \[\033[33m\]\$ \[\033[m\]"
export CLICOLOR=1
export LSCOLORS=ExFxBxDxCxegedabagacad
alias ls='ls -GFh'
alias l='ls -l'
alias md='mkdir -p'
alias ..='cd ..'

alias grep='grep --color=auto -n'

Oracle

select now():
select to_char(sysdate, 'mm-dd-yyyy hh24:mi:ss') "now" from dual;

select last row:

select * from table where id = (select max(id) from table);

Git

Current branch
git rev-parse --abbrev-ref HEAD
awk -F/ "{print \$NF}" .git/HEAD

Log
git log -1
git show 2a32e8590d5c00364b3c025f4c5a08f7aed26fd8
git log -- oneline -- abbrev - commit -- all -- graph

Show
git show f1ec7a9:lib/perl/Module.pm

Show changes history
git log -GMyChangedString -p

Show file history
    commit history
    git log -- filename
    commit history and diffs
    git log -p filename
    tig filename, then j, k, d, q

        To resolve Ctrl+Y in tig:
        stty -a | grep dsusp
        stty dsusp undef
        stty -a | grep dsusp

Rename a branch
git branch -m branch-old branch-new
git push origin :branch-old
git push --set-upstream origin branch-new

Revert a merge to master
git revert -m 1 d33e978a8be12e8023dac8aba2cc126098dfa15d
(where d33e97... is the merge commit)

Revert commit
git revert <hash>

Delete a branch
git branch -D bugfix
git push origin --delete bugfix

Revert branch to remote
git reset --hard origin/bugfix

Resolve a file (ours is HEAD, theirs is trying to merge into HEAD)
git checkout --ours file.c
git checkout --theirs file.c
git add file.c
git commit -m 'File added'

Named stashes
git stash save "guacamole sauce WIP"
git stash apply stash^{/guacamo}

Git patch
git format-patch branch-18 --stdout > 18.patch
git format-patch HEAD^ --stdout > 18.patch
git apply --stat 18.patch
git apply --check 18.patch
git apply 18.patch

Git diff
git diff --stat -p master..branch
git diff branch^..branch
git diff HEAD~1 --stat

Git bisect
git log --since=1.weeks --reverse | head -n3

git bisect start

git bisect bad
git bisect good <hash>
  git bisect run my_script arguments
git bisect reset

Git force push
To force a push to only one branch, use a + in front of the refspec to push
git push origin +branch
git push --force-with-lease origin branch

If git lock occurs
ps -ef | grep git
rm .lock
git fetch --all --prune
(cleans up old branches locally that are no longer on the git remote server)
git checkout branch
git pull

Bring back the removed file

Existing commit

get a list of removed files

git checkout HEAD
OR
git checkout --

then restore needed file

git checkout HEAD file1 file2
OR
git checkout -- file1 file2
OR
git checkout HEAD^ -- file1 file2 file3

Previous commit

git reset HEAD^ -- file1 file2
git checkout -- file1 file2

Previous commits

git reset HEAD~4 -- file1 file2
git checkout -- file1 file2

How many commits is HEAD far away from origin/master?

git rev-list --count HEAD ^origin/master

Clean git dangling objects

git fsck
git gc --prune=now

Rebasing a big big branch

http://blog.appsignal.com/blog/2016/09/27/git-rebasing-strategies.html

Advanced Git commands

https://hackernoon.com/lesser-known-git-commands-151a1918a60

Git notifications link:
https://github.com/notifications/participating

Git pull requests link:
https://github.com/pulls/mentioned

Hide Whitespace Noise:
git diff -w
git show -w
?w=1

Show Changed Words:
git diff --word-diff

Which Branches You Recently Worked On:
recent = ! git for-each-ref --count=10 --sort=-committerdate refs/heads/ --format="%(refname:short)"

Remind Yourself What You’ve Been Up To:
git log --all --oneline --no-merges --author=<your email address>


Current hash:
current = ! git log -1 --pretty=oneline | cut -d' ' -f1
git rev-parse HEAD

Empty commit:
git commit --allow-empty -m "trigger build"

Lines removed so far:
git log --author='Per List' --after='2000-01-01' --word-diff --unified=0 | sed -ne '/^\[-/p' | sed -e '/{+/d' | wc -l

Git CRLF mess:
https://stackoverflow.com/questions/10418975/how-to-change-line-ending-settings