Android O: identify battery sucking apps

Source: Android O: How to Identify and Bitch Slap Those Battery Sucking Apps
On my Oneplus 5T, Android 8.1:

List apps. running in background permanently

• Settings > Dev. Options > Running Services 

Kill the background activity of an app.

• Settings > Apps > Application list > Select app > Battery > Uncheck Background activity

macOS mojave: bluetooth headphones keep on disconnecting

Uncheck "Allow Handoff between this Mac and your iCloud devices" in Preferences | General.

macOS: xcrun: error: invalid active developer path

Source: macOS Mojave: invalid active developer path
If after upgrading from High Sierra to Mojave, you get the following error:

[jerome@jeroboam] > make
xcrun: error: invalid active developer path (/Library/Developer/CommandLineTools),
missing xcrun at: /Library/Developer/CommandLineTools/usr/bin/xcrun

Then re-install xcode developer tools like in:

[jerome@jeroboam] > xcode-select --install
xcode-select: note: install requested for command line developer tools

macOS: from High Sierra to Mojave

Steps:

• Update Clover through Clover Configurator: pick custom install and check
  • AptioMemoryFix-64,
  • ApfsDriverLoader-64 and
  • PartitionDxe-64
• Remove apfs.efi from /Volumes/EFI/EFI/drivers64UEFI: not needed anymore with above Clover options 
• Update kexts in /Volumes/EFI/EFI/CLOVER/kexts/Other
• AppleALC.kext 
• Lilu.kext 
• Replace IntelGraphicsFixup.kext with WhateverGreen
• FakeSMC.kext
• IntelMausiEthernet.kext 

• Download "Install macOS Mojave" application from the Mac App Store, and run it.
• Reboot. At Clover boot screen, choose Boot macOS Install option. Multiple reboots expected. At some time, pick "Boot FileVault Prebooter from Preboot" option to finish the install.
• Update Clover configuration in order to hide the 2 preboot options at boot time. For this, add "Preboot" in Clover Configurator | Gui | Hide Volume
  
• And here it is.
  
• Optional step: Create a Bootable USB with UniBeast

macOS: downloading .gz from Chrome turns into .cpgz

If you download a .gz from Chrome, and double-clicking it simply creates a .cpgz, then the downloaded file is not a .gz
Try

> file --mime-type ~/Desktop/42a3-909a-1b5bdb4a4b8b.gz
text/plain

Then simply rename it into .txt, and you will be able to open it.

macOS: turn text into links automatically

Use Edit > Substitutions > Smart Links

macOS: how to page up with byobu in Terminal.app

Source: How can I page up or down in tmux with Terminal.app?
Terminal.app captures PageUp / PageDown. So, in order to send them to byobu again:
If on a PC keyboard:

• F7
• Shift + PageUp / Shift + PageDown

Or if on a MacBookPro:

• F7
• Fn + Shift + Up / Fn + Shift + Down

Perl: certificate verify failed

Source: WWW::Mechanize SSL connect attempt failed for https get
TL;DR

cpan update Mozilla::CA

git: merge files from another branch

Source: Git tip: How to "merge" specific files from another branch

git checkout [TARGET_BRANCH]
git checkout [SOURCE_BRANCH] my_file1 my_file2

Perl: slurp STDIN

Source: How can I slurp STDIN in Perl?

my $str = do { local $/;  };

macOS: get actual printer IP address

Source: How do I get the actual ip address of a printer in OSX Yosemite

http://localhost:631/printers/

git: rename a branch

Source: Rename a local and remote branch in git

Rename local branch.

git branch -m new-name

Delete the old-name remote branch and push the new-name local branch.

git push origin :old-name new-name

Reset the upstream branch for the new-name local branch.

git push origin -u new-name

macOS: checking for OpenSSL... configure: error: not found

Source: Problem with openssl on macOS
If your ./configure (e.g. for pgbouncer) terminates with the following error despite openssl being installed:

checking for OpenSSL... configure: error: not found

Then, restart it like follows:

./configure --with-openssl=/usr/local/opt/openssl

macOS: listening ports

Source: How can I list my open network ports with netstat?

[jerome@jeroboam] > sudo lsof -PiTCP -sTCP:LISTEN | grep 6432
pgbouncer 10533 jerome    9u  IPv6 0x8678a9be8d9262f5      0t0  TCP *:6432 (LISTEN)
pgbouncer 10533 jerome   10u  IPv4 0x8678a9be9e2f23dd      0t0  TCP *:6432 (LISTEN)

ssh: ssh a remote host via a bastion

Source: SSH ProxyCommand example: Going through one host to reach another server

In order to reach remote1 through a bastion host, add the following lines in your .ssh/config:

Host bastion
HostName bastion-01.golgoth.com
User jgallinari

Host remote1
HostName remote1.toto.swir
User jgallinari
ProxyCommand ssh jgallinari@bastion -W %h:%p

Then ssh remote1 should do it.

macOS: find your CPU

[jerome@jeroboam] > sysctl -n machdep.cpu.brand_string
Intel(R) Core(TM) i7-7700HQ CPU @ 2.80GHz

AWS: Using environment variables in CodeBuild buildspec

Source: Using environment variables in AWS CodeBuild buildspec.yml
See S3_BUCKET below, which is first expanded from ImportValue, then used in BuildSpec.

  AvUsageQuarantineBuildProject:
    Type: AWS::CodeBuild::Project
    Condition: Preprod
    Properties:
      Name: av-usage-quarantine-build
      ServiceRole: !GetAtt AvUsageQuarantineBuildProjectRole.Arn
      Artifacts:
        Type: CODEPIPELINE
        Name: av-usage-quarantine
      Environment:
        Type: LINUX_CONTAINER
        ComputeType: BUILD_GENERAL1_SMALL
        Image: aws/codebuild/java:openjdk-8
        EnvironmentVariables:
          - Name: S3_BUCKET
            Value: !ImportValue delivery-AvDeliveryUtilsBucket
      Source:
        Type: CODEPIPELINE
        BuildSpec: !Sub |
          version: 0.2
          phases:
            install:
              commands:
                - cd ~; wget https://raw.github.com/technomancy/leiningen/stable/bin/lein; chmod +x lein; mv lein /bin
                - LEIN_ROOT=true lein
            build:
              commands:
                - cd $CODEBUILD_SRC_DIR
                - LEIN_ROOT=true lein uberjar
            post_build:
              commands:
                - aws cloudformation package --template template.yaml --s3-bucket $S3_BUCKET --s3-prefix lambda --output-template av-usage-quarantine-output-template.yaml

macOS: Terminal follow focus

Source: Set Terminal Focus to Follow the Mouse Cursor in Mac OS X
Follow focus ON

defaults write com.apple.Terminal FocusFollowsMouse -string YES

Follow focus OFF

defaults write com.apple.Terminal FocusFollowsMouse -string NO

Then, restart Terminal.

Working on High Sierra 10.13.6.

Clojure: transducers from the ground up

Clojure transducers from the ground up: the practice

AWS: !Sub |

• Understanding AWS CloudFormation !Sub Syntax
• What does “!Sub |” mean in AWS UserData field with YAML syntax?

Q: What does !Sub | mean ?
A: This means that you can enter normal looking text without having to use things like "\n" to mean end of line.