curl -sS https://getcomposer.org/installer | php
All settings correct for using Composer
Downloading...

Composer (version 1.6.2) successfully installed to: /root/composer.phar
Use it: php composer.phar

php composer.phar
Do not run Composer as root/super user! See https://getcomposer.org/root for details
   ______
  / ____/___  ____ ___  ____  ____  ________  _____
 / /   / __ \/ __ `__ \/ __ \/ __ \/ ___/ _ \/ ___/
/ /___/ /_/ / / / / / / /_/ / /_/ (__  )  __/ /
\____/\____/_/ /_/ /_/ .___/\____/____/\___/_/
                    /_/
Composer version 1.6.2 2018-01-05 15:28:41

Usage:
  command [options] [arguments]

Options:
  -h, --help                     Display this help message
  -q, --quiet                    Do not output any message
  -V, --version                  Display this application version
      --ansi                     Force ANSI output
      --no-ansi                  Disable ANSI output
  -n, --no-interaction           Do not ask any interactive question
      --profile                  Display timing and memory usage information
      --no-plugins               Whether to disable plugins.
  -d, --working-dir=WORKING-DIR  If specified, use the given directory as working directory.
  -v|vv|vvv, --verbose           Increase the verbosity of messages: 1 for normal output, 2 for more verbose output and 3 for debug

Available commands:
  about                Shows the short information about Composer.
  archive              Creates an archive of this composer package.
  browse               Opens the package's repository URL or homepage in your browser.
  check-platform-reqs  Check that platform requirements are satisfied.
  clear-cache          Clears composer's internal package cache.
  clearcache           Clears composer's internal package cache.
  config               Sets config options.
  create-project       Creates new project from a package into given directory.
  depends              Shows which packages cause the given package to be installed.
  diagnose             Diagnoses the system to identify common errors.
  dump-autoload        Dumps the autoloader.
  dumpautoload         Dumps the autoloader.
  exec                 Executes a vendored binary/script.
  global               Allows running commands in the global composer dir ($COMPOSER_HOME).
  help                 Displays help for a command
  home                 Opens the package's repository URL or homepage in your browser.
  info                 Shows information about packages.
  init                 Creates a basic composer.json file in current directory.
  install              Installs the project dependencies from the composer.lock file if present, or falls back on the composer.json.
  licenses             Shows information about licenses of dependencies.
  list                 Lists commands
  outdated             Shows a list of installed packages that have updates available, including their latest version.
  prohibits            Shows which packages prevent the given package from being installed.
  remove               Removes a package from the require or require-dev.
  require              Adds required packages to your composer.json and installs them.
  run-script           Runs the scripts defined in composer.json.
  search               Searches for packages.
  self-update          Updates composer.phar to the latest version.
  selfupdate           Updates composer.phar to the latest version.
  show                 Shows information about packages.
  status               Shows a list of locally modified packages.
  suggests             Shows package suggestions.
  update               Upgrades your dependencies to the latest version according to composer.json, and updates the composer.lock file.
  upgrade              Upgrades your dependencies to the latest version according to composer.json, and updates the composer.lock file.
  validate             Validates a composer.json and composer.lock.
  why                  Shows which packages cause the given package to be installed.
  why-not              Shows which packages prevent the given package from being installed.

mv composer.phar /usr/local/bin/composer

これで、直接 composer で利用できる。

念の為、アップデート。

composer self-update

実は上記インストール時に、下記２行目の警告が出ていた。

curl -sS https://getcomposer.org/installer | php
PHP Warning:  Module 'intl' already loaded in Unknown on line 0
All settings correct for using Composer
Downloading...

Composer (version 1.6.2) successfully installed to: /root/composer.phar
Use it: php composer.phar

これは、php.ini で extension=intl.so をコメントアウトすることで消えたけど
CakePHP3 をインストールする際に intl は必要なはずなので、後ほど試す。

実は上記起動時に、下記２行目の警告が出ていた。

php composer.phar
Do not run Composer as root/super user! See https://getcomposer.org/root for details

あら、Composer って、root で利用してはいけないのね～。

実行ファイルを移動させて、一般ユーザに戻って利用したら
上記警告は出なくなった。

ちなみに、インストールを root でしたせいか
実行ファイルを移動しておかないと、php composer.phar では、実行できず

php composer.phar
Could not open input file: composer.phar

このように怒られた。。。

WinRoad徒然草：さくらのVPSサーバーにLaravelのインストール（2015-03-23）