composer show --platform

composer_platform.txt

$ composer show --platform
platform:
  ext-apc [3.1.9] : The apc PHP extension
  ext-bcmath [0] : The bcmath PHP extension
  ext-bz2 [0] : The bz2 PHP extension
  ext-ctype [0] : The ctype PHP extension
  ext-curl [0] : The curl PHP extension
  ext-date [5.3.15] : The date PHP extension
  ext-dom [20031129] : The dom PHP extension
  ext-ereg [0] : The ereg PHP extension
  ext-exif [0] : The exif PHP extension
  ext-fileinfo [1.0.5-dev] : The fileinfo PHP extension
  ext-filter [0.11.0] : The filter PHP extension
  ext-gd [0] : The gd PHP extension
  ext-hash [1.0] : The hash PHP extension
  ext-iconv [0] : The iconv PHP extension
  ext-intl [1.1.0] : The intl PHP extension
  ext-json [1.2.1] : The json PHP extension
  ext-libxml [0] : The libxml PHP extension
  ext-mbstring [0] : The mbstring PHP extension
  ext-mcrypt [0] : The mcrypt PHP extension
  ext-mhash [0] : The mhash PHP extension
  ext-mongo [1.2.9] : The mongo PHP extension
  ext-mysql [1.0] : The mysql PHP extension
  ext-mysqli [0.1] : The mysqli PHP extension
  ext-mysqlnd [0] : The mysqlnd PHP extension
  ext-openssl [0] : The openssl PHP extension
  ext-pcre [0] : The pcre PHP extension
  ext-PDO [1.0.4dev] : The PDO PHP extension
  ext-pdo_mysql [1.0.2] : The pdo_mysql PHP extension
  ext-pdo_sqlite [1.0.1] : The pdo_sqlite PHP extension
  ext-Phar [2.0.1] : The Phar PHP extension
  ext-posix [0] : The posix PHP extension
  ext-readline [0] : The readline PHP extension
  ext-Reflection [0] : The Reflection PHP extension
  ext-session [0] : The session PHP extension
  ext-SimpleXML [0.1] : The SimpleXML PHP extension
  ext-sockets [0] : The sockets PHP extension
  ext-SPL [0.2] : The SPL PHP extension
  ext-SQLite [2.0-dev] : The SQLite PHP extension
  ext-sqlite3 [0.7-dev] : The sqlite3 PHP extension
  ext-tokenizer [0.1] : The tokenizer PHP extension
  ext-vld [0.10.1] : The vld PHP extension
  ext-xdebug [2.1.2] : The xdebug PHP extension
  ext-xml [0] : The xml PHP extension
  ext-xmlreader [0.1] : The xmlreader PHP extension
  ext-xmlwriter [0.1] : The xmlwriter PHP extension
  ext-xsl [0.1] : The xsl PHP extension
  ext-zip [1.9.1] : The zip PHP extension
  ext-zlib [1.1] : The zlib PHP extension
  lib-curl [7.26.0] : The curl PHP library
  lib-iconv [1.14] : The iconv PHP library
  lib-libxml [2.7.8] : The libxml PHP library
  lib-openssl [1.0.1.3] : The openssl PHP library
  lib-pcre [8.31] : The pcre PHP library
  lib-xsl [1.1.26] : The xsl PHP library
  php [5.3.15] : The PHP interpreter